some ab initio tudies of the physical properties of materials

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HAL Id: tel-00440923 https://tel.archives-ouvertes.fr/tel-00440923 Submitted on 13 Dec 2009 HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Some ab initio tudies of the physical properties of materials Nathalie Madeleine Marguerite Vast To cite this version: Nathalie Madeleine Marguerite Vast. Some ab initio tudies of the physical properties of materials. Condensed Matter [cond-mat]. Université Pierre et Marie Curie - Paris VI, 2009. tel-00440923

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Page 1: Some ab initio tudies of the physical properties of materials

HAL Id: tel-00440923https://tel.archives-ouvertes.fr/tel-00440923

Submitted on 13 Dec 2009

HAL is a multi-disciplinary open accessarchive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come fromteaching and research institutions in France orabroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, estdestinée au dépôt et à la diffusion de documentsscientifiques de niveau recherche, publiés ou non,émanant des établissements d’enseignement et derecherche français ou étrangers, des laboratoirespublics ou privés.

Some ab initio tudies of the physical properties ofmaterials

Nathalie Madeleine Marguerite Vast

To cite this version:Nathalie Madeleine Marguerite Vast. Some ab initio tudies of the physical properties of materials.Condensed Matter [cond-mat]. Université Pierre et Marie Curie - Paris VI, 2009. tel-00440923

Page 2: Some ab initio tudies of the physical properties of materials

♥srt ♣rés♥té ♣♦r ♦t♥r ♣ô♠

tt♦♥ à rr s rrs

♣été P②sq ♥s s tér①

t ♥t♦ s ♣r♦♣rétés ♣②sqs s

♠tér①

♣r

t ❱

♦t♥ t ♥t r② ♦♠♣♦sé

Pr♦ r ♠rr♦ Prés♥t

Pr♦ ❯ ♦♥ rt ♣♣♦rtr

r rst♦♣ r ♣♣♦rtr

Pr♦ ♣♣♦rtr

r rst♥ ♦① ①♠♥tr

r ♠ Ptt ①♠♥tr

Page 3: Some ab initio tudies of the physical properties of materials
Page 4: Some ab initio tudies of the physical properties of materials

♥sr♣t ♣r♦♣♦s t♦ qr t r♥ ♣♦♠

tt♦♥ à rr s rrs

♦♣s P②ss ♥ ♦ trs

♦♠ ♥t♦ sts ♦ t ♣②s

♣r♦♣rts ♦ ♠trs

t ❱

♥ ♦♥ ② th ♥ r♦♥t ♦ t r②

♦♠♣♦s ♦

Pr♦ r ♠rr♦ r♦♠♥

Pr♦ ❯ ♦♥ rt r

Pr♦ r

r rst♦♣ r r

r rst♥ ♦① ♠r

r ♠ Ptt ♠r

Page 5: Some ab initio tudies of the physical properties of materials
Page 6: Some ab initio tudies of the physical properties of materials

♦♥t♥ts

♦♥t♥ts és♠é r strt

♥tr♦t♦♥ t ♦♥t①t r t é♥ér r té♦rq sr♣t♦♥ s tr① rr

①tt♦♥s étr♦♥qs ♥s s ♦①②s ①t♦♥ étr♦♥q ♥s s s♠♦♥trs ts s ♠tér① rs ♥ ♦r

Pr♦t rr à qtr ♥s P♥ ♠♥srt ♦r♣ ♣tr

② q♥tt② t ♥rs ♦ t ♠r♦s♦♣ tr♥t♦♥ r♦♥ stt t ♦ ♣rtrt♦♥ ♠ ♣♥♥t ♣rtrt♦♥ t♦r② ♦t♦♥ ♦r t♠ ♣r♦ ♣rtrt♦♥ ❩r♦th ♦rr ♥st② ♠tr① rst ♦rr ♥st② ♠tr① ♦♥srt♦♥ ♦ r②st ♠♦♠♥t♠ ♥ ♥ ♥ t tr♦♥ ♥st② P♦ss♦♥s qt♦♥ s♣♦♥s ♥t♦♥ χ0 s♣♦♥s ♥t♦♥ χ ♥rs tr ♥t♦♥ ǫ−1 ♥r rs♣♦♥s ♥ r s♣ r tr ♥t♦♥ ② tr♦♥ ♥r②♦ss s♣tr♦s♦♣②

♦rt rsts tr♦♥ ♥r② ♦ss s♣tr ♥♦♠ ♣s ♣♣r♦①♠t♦♥

♦r② sts ♥ ③r♦♥

Page 7: Some ab initio tudies of the physical properties of materials

♦ ts ♦r② sts ♦ t ♥ ♥s♦tr♦♣②

♦♠♣rs♦♥ t ①♣r♠♥ts ♦♠♣rs♦♥ ♠♦♥ r♥t r②st ♣ss ♥♦♠ Ps ♣♣r♦①♠t♦♥ s ♦♦ ♣♣r♦①♠t♦♥

♦r ♦♥s♦♥

♦rt rsts ♦♣t s♦r♣t♦♥ ①♣r♠♥t

❲t♥ ♥♣♥♥t tr♥st♦♥ t♦r② ♦♥t ♥st② ♦ stts t ♦ ♠tr① ♠♥ts

②♦♥ ♥♣♥♥t tr♥st♦♥ t♦r② ♦ ts s♣rts ts

①t♦♥ ts ♦st♦♥ ♦ ①t♦♥ ts ♦♥ t ts

♦♥s♦♥

♦rt rsts ♦♥ t stt② ♦ ♦r♦♥ rs

♥tr♦t♦♥ t♦♠ strtr ♦ 4 r♦♠ rst ♣r♥♣s

trtr ♠♦s t♦t ♥r② tt ②♥♠s r ♥t s♦♥♥ ♦♥s♦♥s

t♦♠ strtr ♦ ♦r♦♥ rs t ♦r r♦♥ ♦♥♥trt♦♥s ♦r♠t♦♥ ♥r② sss♦♥

tr♥t ♦ t tr♦♥♣♦♥♦♥ ♦♣♥ ♦♥s♦♥

♦♥s♦♥ ♥ ♦t♦♦

♣♣♥s

sr♣t♦♥ ♦ ③r♦♥

② r r♠s ♦♥ r

rr♠ t ❱st r

Page 8: Some ab initio tudies of the physical properties of materials

st ♣t♦♥s ❱st r P♣rs rést♥t ♠s tr① rr ♦rt♦r

s ♦s rrés P♣rs rést♥t ♠s tr① rr

♥r ♦r♣②

Page 9: Some ab initio tudies of the physical properties of materials
Page 10: Some ab initio tudies of the physical properties of materials

és♠é r

♦♥ tté rr ♦♥♠♥t ♥s r♦♣ té♦r ♦rt♦r s ♦s rrés ♦♥r♥ ét s ♣r♦♣rétés s ♠tér①♥térêt ♣♦r ♥s s ♦♠♥s ♥ér ♦ ♥♥♦étr♦♥q ♣♦r ♦t tt♥r ♥ sr♣t♦♥ té♦rq s♥s♣r♠ètr st s ♣r♦sss ♦♥trô♥t ①tt♦♥ étr♦♥q ♥sq r①t♦♥ ♦ és①tt♦♥ étr♦♥q t ♦r

• s ♣r♦♣rétés ♠tèr ♦rs ①tt♦♥ étt ♦♥♠♥t

• s ♣r♦♣rétés étt ①té ♦rés s♦s ♥ s♣tr♦s♦♣ ♣♦r s étr♦♥s ♥

• s rt♦♥s ♦ts s t♦♠s r ♦♣ s étr♦♥st rs ts sr tr♥s♣♦rt étr♦♥q ♦ r①t♦♥ étr♦♥q

s éts rqèr♥t ♥ ♥r♦♥♥♠♥t ♥t♥s t ès ①♦r♥trs r♥ q♣♠♥t t♦♥ ♥t♥s

♥s ♠♥srt st ♦r r♣♣é ♦♠♠♥t r ♦♥t♦♥étrq ♥rs ♥ té♦r ♦♥t♦♥♥ ♥sté é♣♥♥t t♠♣s t q st ♥ ♦♥t♦♥ ♣rt étr♦♥q ♦srés réstts té♦rqs sr ♦♥t♦♥ étrq ♥rs ♥s s ♦①②s♥♦♥ ♦rréés r♣rés♥tés ♣r ♦①② tt♥ 2 t ③r♦♥ ❩r2

s♦♥t érts ♥st s♦♥t ♦♥♥és s ♣r♥♣① réstts té♦rqs ♣♦rs s s♣trs s♦r♣t♦♥ ♦♣tq ♣♦r ♦①② r 2t ③r♦♥ ❩r2 ② ♣rés♥t ♥ ♥♦ ♥tr♣rétt♦♥ tr sr ♥♦② ♣r♠tt♥t ♠♦ésr s ts ①t♦♥qs ♥ té♦r ♦♥t♦♥♥ ♥sté é♣♥♥t t♠♣s ♥♥ s r♥rs s♠♥és sr s rrs ♦r s♦♥t r♣♣és

Page 11: Some ab initio tudies of the physical properties of materials

strt

② tts r ♥ ♥♠♥t rsr ♥ t r♦♣ ♦ t♦r② ♦ t ♦rt♦r s ♦s rrés t ♥s t st② ♦ t ♣②s ♣r♦♣rts♦ s♦♠ ♦ t♦s ♠trs r ♦ ♥trst t♦ t t♦ ♥r rsr ♥ t♦ ♥♥♦tr♦♥s ♦t s t♦ ♣r♠trrsr♣t♦♥ ♦ ♣r♦sss ♦♥tr♦ tr♦♥ ①tt♦♥s ♦r tr♦♥r①t♦♥s s ♦rs

• st② ♦ t r♦♥ stt ♦ ♠trs

• ♥stt♦♥ ♦ t ♣r♦♣rts ♦ t ①t stt r♦♠ t ♣♦♥t ♦ t s♣tr♦s♦♣② ♦ ♥ tr♦♥s

• tt ②♥♠s ts ♦♣♥ t ♣♦♥♦♥s ♥ t t ♦tr♦♥♣♦♥♦♥ ♦♣♥ ♦♥ tr♦♥ tr♥s♣♦rt ♥ tr♦♥ r①t♦♥

s sts ♥♦s ♣r♦r♠♥ ♦♠♣t♥ ♥ rqr ♦♠♣trt♠ r♦♠ ts t ♥ r♥

♥ t ♠♥sr♣t r rst ♦ t ♥rs tr ♥t♦♥ st t♥ t♠ ♣♥♥t ♥st② ♥t♦♥ t♦r② ♥ t ♥t t ♠sr♠♥t ♦ t tr♦♥ ♦ss ♥t♦♥ ♦rt rsts r♣rs♥t ♦r tt♥ 2 ♥ ③r♦♥ ❩r2 r ♥♦rrt ♦①s♥ ♠♥ t♦rt rsts ♦♥ ♦♣t s♦r♣t♦♥ ♦ ♣r♦s ♦① 2♥ ♦♥ ③r♦♥ ❩r2 r ♣rs♥t ♥ ♥tr♣rtt♦♥ ♦♥ t r♥ ♦s t♦ ♠♦ ①t♦♥ ts ♥ t♠ ♣♥♥t ♥st② ♥t♦♥t♦r② s ♣rs♥t ♥② r♥t t♦♥s ♦♥ ♦r♦♥ rs ♥ ♥♣rtr 4 r r

Page 12: Some ab initio tudies of the physical properties of materials

♣tr

♥tr♦t♦♥ t ♦♥t①t r

Page 13: Some ab initio tudies of the physical properties of materials

P ❯ ❳

t é♥ér

♦♥ tté rr ♦♥♠♥t ♥s r♦♣ té♦r ♦♥r♥ ét s ♣r♦♣rétés s ♠tér① ♥térêt ♣♦r ♥ss ♦♠♥s ♥ér ♦ ♥♥♦étr♦♥q ♣♦r ♦t tt♥r ♥ sr♣t♦♥ té♦rq s♥s ♣r♠ètr st s♣r♦sss ♦♥trô♥t ①tt♦♥ étr♦♥q ♥s q r①t♦♥ ♦és①tt♦♥ étr♦♥q t ♦r

• s ♣r♦♣rétés ♠tèr ♦rs ①tt♦♥ étt ♦♥♠♥t

• s ♣r♦♣rétés étt ①té ♦rés s♦s ♥ s♣tr♦s♦♣ ♣♦r s étr♦♥s ♥

• s rt♦♥s ♦ts s t♦♠s rs ♦♣ s étr♦♥st rs ts sr tr♥s♣♦rt étr♦♥q ♦ r①t♦♥ étr♦♥q

s éts rqèr♥t ♥ ♥r♦♥♥♠♥t ♥t♥s t ès ①♦r♥trs r♥ q♣♠♥t t♦♥ ♥t♥s

r té♦rq

♦t é♥ér ♠♥t♦♥♥é sss ♠♣q é♦♣♣♠♥t ♠ét♦s té♦rqs t r ♠♣♥tt♦♥ ♥s s ♣r♦r♠♠s ♥♦r♠tqss ♠ét♦s ♥♠érqs q é♦♣♣ s♦♥t ss♥t♠♥t sés sr té♦r ♦♥t♦♥♥ ♥sté ♦ ❬❪ ts ss s♠ét♦s à ♦r♣s ♣♦r étr s ①tt♦♥s étr♦♥qs

s ♣r♦♣rétés s ♠tér① ♥ésst♥t ér♥ts ♥① sr♣t♦♥ té♦rq s ♣r♦♣rétés ♦♠ ❬❪ ♣r♠ètr ♠ ♦♥st♥ts éstqs ♥ésst♥t étt ♦♥♠♥t étr♦♥qért ♣r s ♣rtrt♦♥s sttqs ts s rt♦♥s rés rst♥ s ♣♦♥♦♥s ❬❪ t rs ♦♥séq♥s t ♦♣étr♦♥♣♦♥♦♥ ❬ ❪ q ♥tr ♥ ♥tr trs ♣♦r s♣r♦♥tté ♦♥♥t♦♥♥ ❬ ❪ rqèr♥t ♣rtrt♦♥ ♦♥t♦♥♥ ♥sté P ❬❪ ♥♥ s ①tt♦♥s étr♦♥qs ♦ ♣rtrt♦♥s ②♥♠qs ♥ésst♥t té♦r ♦♥t♦♥♥ ♥stéé♣♥♥t t♠♣s ❬ ❪

s té♦rs s♦♥t ①ts t sés sr ♦♥♥ss♥ s ♥sté étr♦♥q ♦ ♠tr ♥sté s ts à ♦r♣s s♦♥t rss♠és ♥s ♥ ♣♦t♥t étr♦♥q t é♥ t ♦rrét♦♥ ♦ ♥s éré ♣♦t♥t ♣r r♣♣♦rt à ♥sté étr♦♥q ♥♦②é♥ t ♦rrét♦♥ ♥ ♣rtq ♦♥ ♥ s♣♦s q ♣♣r♦①♠t♦♥s♣♦r ♣♦t♥t ♦ ♥♦② ❯♥ s ♦ts ♦♠♠♥té s♥tq q ♣rt♣é ❬❪ st ♠é♦rr ♥♦② é♥ t

Page 14: Some ab initio tudies of the physical properties of materials

P ❯ ❳

♦rrét♦♥ ♥ ♦♠♣r♥t ré♣♦♥s étr♦♥q ♦t♥ ♥ ♦t♥ ♣r s ♠ét♦s à ♦r♣s à

r à st ♥éssr ♣♦r érr ①tt♦♥ étr♦♥q ❬❪

s ♥s ♥trts ér♥ ♥tr ♣s t é♥r s étts♦♣és ♣r s étr♦♥s t ♣s ss é♥r s étts sés ♥ ♥s s s♠♦♥trs t s s♦♥ts s♦♥t très♦rt♠♥t s♦sst♠és ♥t t q ♣♦t♥t é♥t ♦rrét♦♥ ①t t ♥♦♥♥ ♥ s♦♥t♥té q♥ s②stè♠ ♣ss à ± ♣rts ❬ ❪ tr♠♥t t ♣♦rr ± ♦ù st é♥r t♦t s②stè♠ ♥ ♣s éq♥t té♦rè♠ ♦♦♣♠♥ ♠ét♦ rtr♦ ❬❪ tt s♦♥t♥té st ♣rés♥t q q s♦t ♦♥t♦♥♥ é♥ t ♦rrét♦♥ ♦♥séré ♥s ♣♣r♦①♠t♦♥ ♥sté ♦ ♦ ♥s ♣♣r♦①♠t♦♥ r♥t é♥érsé s ♦♥t♦♥♥s ②rs sés ♥ ♣rt sr ♥ ♣♦t♥té♥ ①t t②♣ rtr♦ ♣rés♥t♥t é♠♥t tt s♦♥t♥té ❯♥ qs♣rt à ♣r ①♠♣ ♥s ♣♣r♦①♠t♦♥ ❲ ❬ ❪ st r♦rs♠♥t ♥éssr♥s ♣rtq s ♥s ♥trts és s ♦♥t♦♥♥s②rs ❨P P s♦♥t ♣s ♣r♦s ①♣ér♥ q sés à ♦

P♦r ♥ ①tt♦♥ étr♦♥q ♥tr ♥ ♣s ♦rrt♦♥ qs♣rt ♣réé♥t ♦♥ ♦t ♣r♥r ♥ ♦♠♣t ♥trt♦♥ étr♦♥ ①té tr♦ q ss rrèr s ts ①t♦♥qs ❬❪ tt ♥trt♦♥ ♠é♥ s tr♥st♦♥s ♥é♣♥♥tst ss ts ♣♥t êtr érts ♣r ♥ ♠t♦♥♥ t ❬❪

♥♠♥t s trs t rs ♣r♦♣rs s♦♥t ♠♣♦rt♥ts

• P♦r r s ♣r♦♣rétés étt étr♦♥q ♦♥♠♥t

• P♦r r ♦♥t♦♥ ér♥t ǫ−1 ♦ ♦♥t♦♥ étrq ♥rs ♥ré♥t ss♥t s ♠ét♦s à ♦r♣s ♣tr

• P♦r r ♣r♦té tr♥st♦♥ s♦s t ♥ ♣rtrt♦♥ rè ♦r r♠ ♣tr

sr♣t♦♥ s tr① rr

♥ ç♦♥ é♥ér s ér♠qs t ♣rtèr♠♥t ③r♦♥ ♥♥① s♦♥t s ♠tér① ♦♥t tst♦♥ s r♥♦rr ♥s s t♥♦♦s ♥érs ér♠qs ♣♦r s rétrs ♥érs é♥ért♦♥

Page 15: Some ab initio tudies of the physical properties of materials

P ❯ ❳

❱ s r♥♦rés ♣r s♣rs♦♥ ♦①②s ♠tér① strtr ♣♦r s♦♥ P♦r ét s ♠tér① s♠t♦♥ ♥♠érq ♦ ♥rô ♣t ♥ s♣♥s ♣s s ①♣ér♥s r s ♠tér① ts♣♦r s ♣♣t♦♥s s♦♥t ♦♠♣①s ♣r ♥♦♠r t♦♠s r♠ éé♠♥tr ♦ ♣r r strtr étr♦♥q ♥♥t ♣r ①♠♣s étr♦♥s d r s ♠tér① tr © s♦♥ tr♦s rt♦♥sq ♣ss ♠♥t♥♥t ♥ r

s éts sr s ①tt♦♥s étr♦♥qs ♦ré ♥ ♠♣♥stt♦♥ t♦t♠♥t ♥♦ s♦s rt♦♥ ♥♥Ps sr s ♦♥ss ♠ Ptt ♦♠♥é s ♥♦s ♦♥♥ss♥s s qss sr s ♣♦♥♦♥s ♣♥♥t ♠ tès t ♥s♥é ♥s ♦♠♣ré♥s♦♥ rô ♦♣ étr♦♥♣♦♥♦♥ ♥s r①t♦♥ étr♦♥q ♥♥ t♦♦rs ♠♥é ♥ ♣rè ♥ tr sr s rrs ♦r ♠tér① q ♦♥♥ss♥t ♦r ♥ r♥ ♥térêt ♣rt ♦♠♠♥té s♥tq tt ♦♥♥ss♥♥♥♥ ♣♣♦rt ♦r ♥ r♦♥♥ss♥ ♥tr♥t♦♥ à éq♣q ♥♠ ♦♠♠ ♥q♥t s tt♦♥s ré♥ts ♥♥① str① ♠♥és ♣♥♥t ♠ tès

①tt♦♥s étr♦♥qs ♥s s ♦①②s

r té♦rq rt à tt ♣rt st ①♣té ♥s s ♣trs t s ♣r♥♣① réstts s♦♥t ①♣qés ♥s s ♣trs t ♦♥♥ ♥ ♣rç ♠s tr① rr ♥ ①♣q♥t ♦♥tr

♠♦♥ rré ♥ étt ♥ ♦rt♦r ré♣tt♦♥ ♥tr♥t♦♥ ♣♦r s é♦♣♣♠♥ts té♦rqs sr s♣tr♦s♦♣ s étr♦♥s ♥ ♠♣sés ♣r ♥♥ rs♣♦♥s r♦♣ té♦r ② ♦ré ét s ①tt♦♥s étr♦♥qs ♥ srs ♠tér① ♥térêt ♣♦r ♥ ♠♥♥t s ♣r♠èrs ♣♣t♦♥sà s ♦①②s ♠ét① tr♥st♦♥ ♠♥t ♦rréés 2 t ❩r2s ♠ét♦s té♦rqs sqà ♣♣qés à s s♠♦♥trs t s♠ ♦♥t ♥éssté s ♠é♦rt♦♥s ♥ rs♦♥ ♦st♦♥ ♣sr♥ s étr♦♥s ♥s s ♦①②s

♦♥t♦♥ ♣rt é♥r −ℑ(ǫ−1) ♣r♠t ♠ttr ♥ é♥ s①tt♦♥s étr♦♥qs ♦ts s ♣s♠♦♥s ♥ sért

−ℑ(ǫ−1) = −ℑ(1 + vχ),χ = χ0 + χ0(v + fxc),

♦ù v st ♣♦t♥t ♦♦♠♥ χ0 st ♦♥t♦♥ ré♣♦♥s étr♦♥s♥é♣♥♥ts t fxc st ♥♦② é♥ t ♦rrét♦♥ été ♦♠♣ré à s ♠srs très ♣réss ♣rt é♥r étr♦♥q ❬❪ ♣r P tts♥r ❯♥rsté ♥q ❱♥♥♥ tr ♠♦♥tré r♥ ♠♣♦rt♥ s ts ♠♣s ♦①

Page 16: Some ab initio tudies of the physical properties of materials

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χ0v ♥s ré♣♦♥s à ①tt♦♥ s étr♦♥s ♦sés p Ps ♦♦ré à ér♥ts éts sr rô s ♠♣s ♦① ♥s ré♣♦♥s ♥♥♦ts r♦♥ ❬❪ ♦ ♥s rér♥♥ ♥♥♦strtrss♠♦♥trs ♥ ♦♥r♥t tès ♦tt ❬❪

♥st tré sr ♦①② ③r♦♥♠ s t Pr♥ ♦♠♣rs♦♥ s ♦♥♥és ①♣ér♠♥ts ♦t♥s ♣r ♥ ♦♦rt♦♥ ②♥t ♦ t♦♥ ♣érr tr♦♠t tr♦♠étr r♥♦ sr s ér♥ts ♣ss rst♥s ❩r2 ❬❪ ♥♦s ♣r♠s étr♠♥r q ♥ té♦r st ♥éssr♣♦r trtr ç♦♥ ♣♣r♦♣ré s s♣trs ①tt♦♥ étr♦♥q ♥ss ♦①②s ❬ ❪ ♥ ♦♥ té ♣♦r s♣tr♦s♦♣ ♣rt é♥r t éé s ♣rs♣ts érts ♥s st♦♥

♦♦ré ③qr♦ r♦tt ②♥r♦tr♦♥ t rrtt P ♥s r tès té♦rq r♥ sr ♦①② r ♦♥ré ♥♥ s ♠srs ♣♦t♦é♠ss♦♥ rés♦ ♥ ♥ ♦ P ♦♥t ♣r♠s ♠♦♥trr ç♦♥ ♥tt♥ ♥ss♥ s rs ♣r♦♣rs ♦t♥s ♥ ♦♠♠♣♦♥t é♣rt qs♣rt ♦r♥té tr r♥ rs ♥ trt♠♥t ♠é♦ré ❬❪ ♦♥t♦♥ ér♥t ǫ−1s é♦♣♣♠♥ts r♥ ❬❪ ♦♥t ♣r♠s ♥ ♣rtr strtr étr♦♥q 2 t s♣tr s♦r♣t♦♥ ♦♣tq ❬❪

s tr① ♦♥t ♥ ♦tr ♣r♠s ♠♦♥trr q ♦♥t♦♥ ♦♥étr♦♥q qs♣rt èr ♣ tr ♣r♦♣r ♥s s ♠tér① r ❬❪ ♦ 2 ❬❪ ♣♦♥t ♦♥♠♥t r♥ ♥s ét sé sr r①t♦♥ étr♦♥q♥s ♥ ♦♥t♦♥

①t♦♥ étr♦♥q ♥s s

s♠♦♥trs

r té♦rq tt ♣rt st ①♣té ♥s ♥♥① t ♥s s♣t♦♥s tés

s ♠é♥s♠s és①tt♦♥ étr♦♥qs s♦♥t ♠♣♦rt♥ts t♥t ♣♦♥t ♦♠♣♦rt♠♥t s ér♠qs s♦s rrt♦♥ q ♣♦r tr♥s♣♦rt ♥s s ♥♥♦s♣♦sts r ♦♠♣r♥r s ♠é♥s♠s r①t♦♥ ♠♣q ét ♦♣ étr♦♥♣♦♥♦♥ ♥s ♥ ♦♥t♦♥

sqà ré♠♠♥t ♦♣ étt éé ♥s s s♠♦♥trs s ♠♦ès stés sr ①♣ér♥ ♣♦st♦ st ♣r♠s é♦♣♣r té♦r ♥t♦ ♦♣ ① étts étr♦♥qs

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♥ ♦♥t♦♥ ♥ ♣♦♥♦♥ tr ♦♥ ♥ ❬❪ tr été ♠♥é ♥ ♦♦rt♦♥ Pr♦ ❱ ②tr ❯♥rsté Pé♦q ♦♠s ss ♦r♥té s rrs rs ♥tr♣rétt♦♥①♣ér♥s s♣tr♦s♦♣ rés♦ ♥ t♠♣s ❬ ❪ s r♥èrs ♦♥♥♥t ès ① ♣r♦sss ♥trt♦♥ ♠r♦s♦♣q ♦♥♠♥t① t ♦♣ étr♦♥♣♦♥♦♥

♥s s s♠♦♥trs ♣rés♥t♥t ér♥ts ♠♥♠ és ♥s ♥ ♦♥t♦♥ ♦♣ étr♦♥q ① ♣♦♥♦♥s ♦♥r♦♥ ♥ ♣r♠t tr♥srt étr♦♥q ♥ é à tr t ♦♥trô tr♥s♣♦rt étr♦♥q ♥s s ♥♦s ♦♥s ♦r ♠♦♥tré q♥♦s ♣♦♦♥s ♣rér s ♦♥st♥ts ♦♣ à ♣rès ♣♦r s♦♥ é Γ à é X rs♣♦♥s t ♥♥ ❬❪ st♥ ♥é ♦♥sér ♣r r♣♣♦rt ① érts tr♦és ♥s ttértr①♣ér♠♥t

♥♥ ♥s P ♥♦s s ♦♥t ♣r♠s ér t♠♣s ①tt♦♥ t rtr s ♦♥♥ss♥s ts ♥ ♠♦♥tr♥t qs♣♦♥♦♥s ♠t♥t ré♠♥t t♠♣s ①t♦♥ ❬❪

s sès s ① tr♦s ♠♠rs éq♣ ♣r♠tt♥t ♥srér♥ts rt♦♥s trs st♦♥

ts s ♠tér① rs ♥ ♦r

r été tt tté ♣t êtr tr♦é ♥s s réér♥s❬ ❪ s r♥rs réstts ♣és s♦♥t ♦♥♥és ♥s ♣tr

♥♦② ♦r 10 st ♥ ①♥t s♦rr ♥tr♦♥ t ♥té ♠♦♥ ♥térêt ♣♦r ♦r t s ♠tér① rs ♥ ♦r tr ♣rts éé♠♥ts ♦r♠♥t s ♠tér① trrs à s s s♦♥s♦♥ts ♦rt♠♥t rt♦♥♥s

t♥t t trs♥t ♥r t ❬❪ s ♦♠♣♦sés rs ♥♦r ... s♦♥t s ♠tér① très rs q ♠ért♥t s éts ♦♥t♥s❯♥ ♦rt tté rr sr s ♠tér① ♣rtèr♠♥t ♣♦♥ ♥s s rrs s s ♥t♦ ♥♦♠r sqs① q ♠♥és ♣♥♥t ♠ tès ❬ ❪ ♦♥t ♥ r♥ rô

♥s ♣ssé ♠ ss ♥ t ♥térssé ♥ ♦♦rt♦♥ ③③r ss♦♥ r♦♥ t ❩ér ① ♣r♦♣rétés rt♦♥♥s ♦r ❬ ❪ t rr ♦r ❬❪ s tr① s♦♥t ♥tés ♥s ttértr ♦♠♣rs♦♥ ♥♦s s ♥t♦ ♦t♥ssr s strtrs ②♣♦tétqs s ♦♥♥és ①♣ér♥ ♠srés♥ s♦♥ ♠♥ t ♥ s♦r♣t♦♥ ♥rr♦ ♥♦s ♣r♠s rs ♥rtts sr ♦st♦♥ s t♦♠s r♦♥ ♥s strtr

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♦r t étr♠♥r strtr t♦♠q rr ♦r 4♦♠♠ ♥ ♦sèr 11p t ♥ î♥ q ♠ ♣r♠t ♠ttr♥ qst♦♥s s réstts ré♥ts ❬❪

Ps ré♠♠♥t ♥ ét♥t s s♣trs rés♦♥♥ ♠♥étq ♥ér ♥ ♦♦r♥t r P ♥sttt ♥ér♦t P②sq s ① ♦♥♥sés ❯♥rsté Prs ❱ P r strtr t♦♠q rr ♦r 4 q s étr♠♥é ♣♥♥t ♠ tès ❬ ❪ été ♦♥r♠é ♣r s ♥♦s éts ❬❪t ét strtr ♣s ♦r♥t ♥s ♠tér été ♥té ❬❪

♥♥ st ♠♥t♥♥t ♦♥♥ q ♦r ♣r à t ♣rss♦♥ ♠étst ♥t s♣r♦♥tr ❬❪ ♦r♥ tt tr♥st♦♥ st ♣♥♥t♥♦r à étt ②♣♦tès ♥ ♥♦ ♣s 28 ♥♥t êtr é♦rt ❬❪ P♦r rr ♦r ♥♦s ♦♥s ♣rét ♣♦r ♠tér q ♦♣ ♣r s tr♦s r♥ ♠étq à ♣rss♦♥ ♠♥t ♥t♠♣értr s♣r♦♥tté éé ♣♦r ♥ s♣r♦♥tr ♣r♦ 2 ❬❪

♥②s ttértr ré♥t ❬❪ ♠♦♥tr q ét ♦r♠t♦♥ s rrs ♦r t r stté s♦è ♥ ♥térêt ♦♥t♥ tq qst♦♥ ♥st ♣s rés♦ ré♠♠♥t ❬❪ é ♥ ♦♦rt♦♥ ♥ st t ♠♠♥ tr♥♥② é♥r ♦r♠t♦♥ ér♥ts strtrs t♦♠qs s é♥rs és ♠♦♥tr♥t ç♦♥ ♥tt♥ q ♣♣rt s rrs ♦r étés ♦♥t ♥ t♥♥ à s é♦♠♣♦sr ♥ ♦r r♣t ♣rt rr ♦r 4♥♦s ♦♥s tr♦é s♠♥t ♥q strtrs q s♦♥t sts t ♣♥t s♦r♠r ❬❪ ♣tr s strtrs s♦♥t ♠étsts ♣r r♣♣♦rt rr ♦r 4 st s ♠ éé♠♥tr 132♦rsq st ♠♦ésé ♣r ♥ ♦sèr 12 t ♥ î♥ ♦s ♥♦♥s ♦♥ q tt ♠étstté ①♣q té à s②♥tétsr sé♥t♦♥s ♣r♦♣rs 132 ①♣q ss s♥ é♥t♦♥♠♦♥♦rst♥

♥ q 4 ♣rés♥t ♠t éstq ♦♥♦t ♣s ♠♣♦rt♥t ♦♥♥ ♣r♠ s ér♠qs ≈ P s♦♥ tst♦♥♦♠♠ ♠tér ♥ rst ét r ♥ ♣t résstr à ♣r♦♣t♦♥ ♥ ♦♥ ♦ ♦♠♠ é♠♦♥tr♥t s ♦♥♥és ①♣ér♠♥ts ré♥ts ❬ ❪ ♣♥♥t à r t ♠é♥s♠ ♠ê♠ ré♣♦♥s à ♥ ♦♠♣rss♦♥ ②♥♠q ♥st ♣s ♦♠♣rs ♥s ♣rt résst♥ ♣ êtr ss♦é à ♥ ss ♦♥tr♥t s♠♥t❬❪ ♠s tt ♥tr♣rétt♦♥ été ♦♥tsté ♣r st ♣r ♥ ①♣ér♥ ♠♣ts ♣r♦ts sr s ❬❪ ♥s tt r♥èr ①♣ér♥ ♠♦t♦♥ ♦♠♣♦rt♠♥t s♦s ♦♥t♦♥s ①trê♠s ♥ ♣s ♣ êtr♦♠♣rs ♣t êtr ttré à ♥ ♣r♦♣rété ♣②sq ♥tr♥sèq rr ♦r 4 ♦ à ♥ ♦ ♣srs tr♥st♦♥s ♣s ❬❪

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tr ♣rt ♥ ♣r♦sss ♠♦r♣st♦♥ 4 été séré à ♣rtr ♦srt♦♥ ③♦♥s ♥♦♠♠♠♥t ♥s s ③♦♥s ♥tr s r♥s 4 ♥ ①♣qr s ♠♦t♦♥s s ♣r♦♣rétés ♠é♥qs ♦srés ♦rs ♥ ♦♠♣rss♦♥ ②♥♠q ❬❪ s ③♦♥s ♦♥t é♠♥t été♦srés ♦rs ①♣ér♥s ♥♥♦♥♥tt♦♥ ❬❪ ♦ sr s é♥t♦♥s②♥t s ♥ ♦♠♣rss♦♥ ♥♦♥ ②r♦sttq ♥t sqà P ❬❪s ③♦♥s ♦♠♠ ♦srés ♥ ♦♥r♥♥t ♣♥♥t q♥ rt♦♥ ♦♠ ♠tér t s ♥tr♣rétt♦♥s ♠♦r♣st♦♥q s♦♥t ♦♥♥és s♦♥t ♦♥trt♦rs ♥tr s rt♥s s s♥t sr ♣rés♥ ♦r t r♦♥ ♠♦r♣ ❬❪ trs ② ♦♥t rr ♦r 4 ♠♦r♣ ❬ ❪ ♣s s ①♣ér♥s ♠♣t srs ❱♦r t ❬❪ ♥♥s♥t ♣s ♣rés♥ ♣ss ♠♦r♣s

ét ♥ ♦rs ♣r♠s ♥tr trs r ♦♠♣♦rt♠♥t s♦strès t ♣rss♦♥ s ♣ss ♣réé♠♠♥t ♥tés ♦♠♠ sts ❬❪♦s ♦♥s tr♦é q ♣rés♥ ♥s ♦r ♥s î♥ ♥t ♥ ♠♦t♦♥ ♦♠♣♦rt♠♥t ♠é♥q rr ♦r ♥t ♠s été été ♣r♥t ♦s ♦♥s ♠♦♥tré q

4 t q ért sss ♣t s♦t♥r s ♣rss♦♥s ♦rr r s♥s tért♦♥ s ♣r♦♣rétés ♠é♥qs

♣rés♥ ♥ ♦r ♥s î♥ ♥t ♥ ♠♦t♦♥s ♣r♦♣rétés ♠é♥qs ♣r ♦r♠t♦♥ ♥ s♦♥ î♥ à① t♦♠s

♦tr ♥tr♣rétt♦♥ à ♥♦♥tr ♥ ♣♣r très ré♥t ❬❪s♦♥ q ♥ ♣rss♦♥ ♥① ♣ î♥ t ♣r♦♦q ♥♠♦t♦♥ s ♣r♦♣rétés ♠é♥qs ♥s 4 ♣r ♦s ♣r♠rs réstts ♦♥r♥♥t ♣♣t♦♥ ♥ é♦r♠t♦♥ ♥① é♠♥t♥t sréstts ét ♥ ♣ t♥q ♠♣♦rt♥ts ♦♥séq♥s ♥s♥♦tr s ♦♥ ♣t ♣r ♠s t♥ ♠é♥q s♦s ♣rss♦♥ ♥♠é♦r♥t s②♥tès ♠tér ♦rs q ♥s s ❬❪ ♠s t♥ ♠é♥q st ♥ ♣r♦♣rété ♥tr♥sèq ♠tér ♦séts ♥ ♦rs s♦♥t st♥és à rr ♣♦♥t

Pr♦t rr à qtr ♥s

♥s r ♦t é♥ér ♦♥♥é ♥ ♣r♠èr st♦♥ ♥ ♣r♠èr rt♦♥ rr été ♣ é♦qé t ♦♥r♥ s ♣r♦♣rétés étt ♦♥♠♥t ♠♣q ♦♠♣r♥r s ♠ts ♥s s ♣rés♦♥ sr é♥r t♦t

tr♦é ♥s s s q ♣s éqr ♥st ♣s ♣s♦sré ♥s s ♠ét① ts tt♥ ♦ ③r♦♥♠ ♦ ♥ ♦①② t

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q 2 t trs ♦♥t tr♦é ♥ ♣r♦è♠ ③r♦♥ ♥ ♥♥① ♥ trs tr♠s r♠♠ ♣s ♣rét ♣r st rr♦♥é s ér♥s é♥rs ♥tr s ♣ss s ♠tér① téss♦♥t très ♣tts

♦♥ ②♣♦tès é♦ré ♦rs tès ❱ r♥té éqt sr tt♥ ❬❪ ♦♥ré r ②♦♥ t ♥ ♦♥♦ t ♣rès ♥♦♠rss sss♦♥s s♥tqs rss ♣rs♦♥♥tés st q ♣rét♦♥ s ér♥s é♥r ♥ st ♠té ♣r ♥rtts ♣♣r♦①♠t♦♥s ♣♦t♥ts é♥ t ♦rrét♦♥ ♣♦r s étr♦♥s ♥ r à ♣♦r s ♠ét① ♥ ts♥t ♥ ♣♦t♥tsé sr é♥ ①t st ♥ tâ ♠ts q ♣rés♥t réstés t ♥ésst s é♦♣♣♠♥ts té♦rqs t s s♠t♦♥strès ♣réss tr st ♥ ♦rs ♥ ♦♦rt♦♥ ❱ r♥té♠♥t♥♥t rr ♣r♠♥♥t à ès

s ♣r♠rs réstts ♦t♥s ♥ é♠r ♠♦♥tr♥t q♥ ♦♥t♦♥♥ t②♣ P à s é♥ ①t ♥ ♣r♠t stsr ♣s α ♥ ♣r♦t étr s s ♣r♦t s ♠♦t♦♥s s♥ts éqt♦♥ étt é

s éts sr s ♦rrs s♦sst♦♥ ♦♥t s ♣♦rsr 4st très tsé ♥s ♥str t ♥s r♠♠♥t rté ♥t st♣rès ♠♥t t ♣r♠t s♦♥ tst♦♥ ♦r♥t ♥s s ♦ts ♦♣ t ♥ ♦s ♦♥s réé à ♦♠♥r s ♣r♦♣rétés rté t s♣r♦♥tté ♥ ♦♣♥t ♥ tr♦s rr ♦r ❬❪ ♦♥♥t étr s rrs ♦r s♦s ♥ r stté q♣r♠ttrt ♦♠♣r♥r stté ♠tér ♦rs ♦♣ ♦♣ ♣r♠ttr ♦♠♥r rté t s♣r♦♥tté ♦♠♥s♦♥ ♥s ♥ ♠ê♠ ♠tér s♣r♦♥tté t ♥ ♦rt rtést ①trê♠♠♥t ♥térss♥t t♥t ♣♦♥t ♦♥♠♥t q s ♣♣t♦♥s q ♣♦rr♥t ♥ é♦r ❯♥ ♣r♦t r♥♦♣♦♥s ♦♥r ❯♥rsté s é♠rré ♣♦r ♦♣r ♦r ②♣♦tès♥♣♣♦♥ ❬❪ ♦ rr ♦r ②♣♦tès r♥çs ❬❪ ♦t♦r♥t♣♦♥s r♦ r été rç ♥ t sr ♥♦r ♣♥♥t ♣srs ♠♦s ♥

tr ♣rt s éts sr s ♦rrs s♦sst♦♥ ♦♥t s ♦♥t♥r ♥ ♣r♠r ♦t ♦♠♣r♥r strtr t♦♠q srrs ♦r rs ♥ ♦r st tr♦r ♥ rtérstqs♣tr♦s♦♣q ① ♥s ♥ ♣♦♦r s éttr ♥s s é♥t♦♥s ❯♥ ♦♦rt♦♥ ♥s ♠qs ♥♥s tt P♦ès st ♥sés ♥s q ♦r ♣♦r s②♥tès sé♥t♦♥s ♥♦r srr t♦♥ ♥sttt ♦r trs ♥ ❲P trs ♥♦rtt♦♥s ♥tr ♥♦r ♣rt♦♥s r trt s ♣♥ t st

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♥tst t♦♥ ♥sttt ♦ ♥ ♥ ♥♦♦② P♦② P ❯♥ ①è♠ ♥ st ♠é♦rr t♥ s♦s ♦ s♠tér① ♥ ② ♥tr♦s♥t s ♦♣♥ts ♣♣r♦♣rés

ét sr és①tt♦♥ étr♦♥q s♦sst♦♥ ♦♥t♥r t tt té♠tq s r♥♦rr ♥ ♣rtr râ rrt♠♥t♣r st ♥ st♦♥ ♥ t♦r tt té♠tq rç s♦t♥ ♣r ♥♥♠♥t P ♣r♦t r P ♥sttt ♥ér♦ t P②sqs ① ♦♥♥sés ❯♥rsté Prs ❱ P r t t♦ ♥♦ r♥♦

s éts ♦♥t ♦r êtr ét♥ rr s♠ t ① s♦♥ts♠tér① ♥térêt ♣s s ♣♦♥♦♥s r♥ ♦♥r♦♥ ♥tr♥♥♥t ♥s r①t♦♥ étr♦♥q t ♥s tr♥s♣♦rttr♠q t ♥♦s s♦♥s q ♥ s ♥① ♥♥♦étr♦♥q st s♦t♦♥ s ♣r♦è♠s é♠♥t ♦s ♦♥s ♥ ♣r♦t

ét♥r ♠ét♦ ♦♣ s ♣♦♥♦♥s ♦stqs ♥tr ③♦♥ té♦r ♦t êtr ét♥ r s ♣♦♥♦♥s s♦♥t♦♠♣♥és ♥ é♦r♠t♦♥ éstq

étr ♦♣ ♠♣ étrq réé ♣r s ♣♦♥♦♥s♦♣tqs ♥s s ♠tér① ♣♦rs ♦♣ rö

étr s ts ♥♥♦strtrt♦♥ sr ♦♣ étr♦♥♣♦♥♦♥ ♦r sr s s♣rrés① ♣s sr s s s♠♦♥trs

s ① r♥rs ♣♦♥ts s♦♥t ♦♥♠♥t① ♥s ♣r♦t st tr ♣rt ♣♣♦rt ♥ ♥♦ ♠ét♦ ♣♦r rs éé♠♥ts ♠tr ♦♣ étr♦♥♣♦♥♦♥ s ♦♥t♦♥s ❲♥♥r r ♣r♠ttr éérr ♥r P ❯♥rsté Prs ❱ P r s ♦♥t♦♥s ❲♥♥r s♦♥t ♠♥t♥♥ttsés é♠♥t ♥s qs♣rt ♥ ❲ q ♣r♠t♥ ♥ ♠♣♦rt♥t ♥s t♠♣s é①ét♦♥ s ♣r♦r♠♠s ❬ ❪

♥♥ s ①tt♦♥s étr♦♥qs s♦sst♦♥ t s s♣trs ♣rt é♥r étr♦♥q s♦♥t t♦♦rs ♥térêt ♣r ♥ ♥♦♠ét♦ ♥ ♦♣ ♣s q s♣♣ sr rés♦t♦♥ éqt♦♥ ♦ ❬❪ ♦♥ ♠♦ ♥térêt à ♦♥ tr♠ tt♦r♥tt♦♥ st q s♦t♦♥ éqt♦♥ ♦ st s ♥éqt♦♥ ♦③♠♥♥ ♦♠♣èt♠♥t q♥tq ♣r♠tt♥t ♠♦ésrà ♦s tr♥s♣♦rt étr♦♥q ♥♦ér♥t q ♥♦s ♦♥st♥ts ♦♣ étr♦♥♣♦♥♦♥ ♦♥tr♥t t tr♥s♣♦rt ♦ér♥t ❬❪ tr♣rt ♣t êtr ♦♣é s é♣♠♥ts t♦♠qs

Page 22: Some ab initio tudies of the physical properties of materials

P ❯ ❳

♠t♦♥ à tr♠ st ♥ t ♣rér r①t♦♥ t♦♠q ♣r♦t ♣r ①tt♦♥ étr♦♥q ♦♥ r ♦rs ♥ sr♣t♦♥ ♥t♦s ts rrt♦♥ t s éts ♣r♦ts ♣r rrt♦♥

P♥ ♠♥srt

st♦♥ s♥t rr♦♣ ♦r♣ ♣r♦♣r à ♣tr ♥q♠♥t

Pr ♦♠♠♦té t é♠♥t ♣♦r ♥tér♥r t q ♥s st ♥♦tr♥ tr s ♣trs s♥ts s♦♥t ♥ ♥s

♣tr rr♦♣ ér♥ts ♥♦ts tr q ♣r♠tt♥t ♦♠♣r♥r ♦♠♠♥t st é ♦♥t♦♥ étrq ♥rs ♥ t q st ♥ ♦♥t♦♥ ♣rt étr♦♥q ♦sré ♦rérr s ♣r♥♣① réstts ♥②♥t tr♦é ♥ ♣rt ♥s ttértr ♠♥♠♥t ♦♠♣t ♦♥ s♦t st q s ♥♦ts s♦♥t ts♥s ♦r♠t♦♥ s ♥s s♥tqs q ♥rr

♣tr ♦♥♥ s ♣r♥♣① réstts té♦rqs sr ♦♥t♦♥ étrq ♥rs ♥s s ♦①②s ♥♦♥ ♦rréés s réstts ♣tr ♣r♠tt♥t ♦♠♣r♥r q t ♣♣r♦①♠t♦♥ ♣ss♠♣ ♣s ét♦r ♦ P s♦♥t s ♣♣r♦①♠t♦♥s éqts♣♦r r s s♣trs ♣rt é♥r étr♦♥q s étr♦♥s ♥ ♠é♦rt♦♥ rés♦t♦♥ s ①♣ér♥s ♣rt é♥rétr♦♥q st ♣r♠♦r ♣♦r étr ç♦♥ ♥ ré♣♦♥s s étr♦♥s ♥ ♣r ①♠♣ ♦rsq rst ♣rés♥t ér♥ts ♣ssrst♥s

♣tr ♦♥♥ s ♣r♥♣① réstts té♦rqs ♣♦r s s s♣trs s♦r♣t♦♥ ♦♣tq ② ♣rés♥t ♥ ♥♦ ♥tr♣rétt♦♥ tr sr ♥♦② ♣r♠tt♥t ♠♦ésr s ts ①t♦♥qs ♥té♦r ♦♥t♦♥♥ ♥sté é♣♥♥t t♠♣s

♥♥ ♣tr rés♠ s r♥rs s ♠♥és sr s rrs ♦r ♣tr st ♥ t ♥ rt r ért st à ♥ ♦♥ér♥♥té th ♥tr♥t♦♥ ②♠♣♦s♠ ♦♥ ♦r♦♥ ♦rs ♥ ttrs ♣t♠r ts ♠♥ ♣♥

♥♥ ♥s s ♥♥①s érs s ér♥ts ♣ss ③r♦♥♥♥① rér rè ♦r r♠ ♥♥① ♣rés ♠♦♥rr♠ t ♥♥① t ♠ st ♣t♦♥s ♥♥① ♥t ♦♥♥r ♦r♣ é♥ér q rr♦♣ ♣trs ts s♥ts

Page 23: Some ab initio tudies of the physical properties of materials

P ❯ ❳

♦r♣ ♣tr

❬❪ ❲ ♦♥ ♦ trs ♠str② ❲♦r ♥t Ps♥♦ ♥♣♦r

❬❪ ♦♥s ♥ ♥♥rss♦♥ ♥st② ♥t♦♥ ♦r♠s♠ ts ♣♣t♦♥s ♥ ♣r♦s♣ts s ♦ ♦r♥ P②ss

❬❪ P ♥♥♦③③ r♦♥♦ P P♦♥ ♥ r♦♥ ♥t♦ t♦♥♦ ♣♦♥♦♥ s♣rs♦♥s ♥ s♠♦♥t♦rs P②s

❬❪ r ❩r♦ r♦♥♦ ♦ ♥ ♦♥ P♦♥♦♥s♦t♥♥ ♥ s♣r♦♥tt② ♥ tr♠ ♥r ♣rssr P②s

tt

❬❪ st ❱st ♥ ❱ ②tr ♥t♦ ♠t♦ ♦r t tr♦♥♣♦♥♦♥ sttr♥ t♠s ♥ s♠♦♥t♦rs ♣♣t♦♥ t♦ s ♥ PP②s ttrs t ② t ♠r♥ P②s♦t② ♦r t ♥r② ss ♦ ❱rt ♦r♥ ♦ ❯trst ♥tt♣trst♦r

❬❪ tt♦ ♥r t ❱st ♥ r♥s♦ r ♣r♦♥tt②r♦♠ ♦♣♥ ♦r♦♥ ♦sr P②s

❬❪ ♥ ♥ ❯ r♦ss ♥st②♥t♦♥ t♦r② ♦r t♠♣♥♥ts②st♠s P②s tt

❬❪ ❯ r♦ss ♥ ❲ ♦♥ ♦ ♥st②♥t♦♥ t♦r② ♦ rq♥②♣♥♥t ♥r rs♣♦♥s P②s tt

❬❪ ♥ ♦tt r♥s♦ ♦tt t ❱st ❱r♦ ♥♦ ♥♥ ♥srst♥ ❲ssr ♥ ♦ ♦♥♥ ♥ ♦♦♦ ♦ ♥ ❲ ♦② ♦♥r♥ ♦♥trt♦♥ t♦ t ①♥♦rrt♦♥r♥ ♦ t♠♣♥♥t ♥st② ♥t♦♥ t♦r② P②s

❬❪ ♥ ♥♥ ♥ ♦ tr♦♥ ①tt♦♥s ♥st② ♥t♦♥ rss ♠♥② ♦② r♥s ♥t♦♥s ♣♣r♦s ♦ P②s

❬❪ ❲ ♦② ütr ♥ ♠ ♥r② ♦♣rt♦rs ♥①♥♦rrt♦♥ ♣♦t♥ts ♥ s♠♦♥t♦rs P②s

❬❪ ♥♥♦♦ ütr ♥ ♠ t♦♥ ♦ t ♦♥s♠♣♦t♥t ♥ ts s♦♥t♥t② ♦r ♠♦s♠♦♥t♦r P②s

❬❪ ♥ ♥ ♥qst ♦ stt ♣②ss ♦♠ ♣ ♠ Prss ❨♦r

❬❪ ♥ P②s

Page 24: Some ab initio tudies of the physical properties of materials

P ❯ ❳

❬❪ rt ♥♥ ♦ ♥ ♥ P②s tt

❬❪ ♥t r② ♥ ♦♥ ♦r② ♦ ♦♣t s♦r♣t♦♥ ♥♠♦♥ ♥ s P②s

❬❪ ♥t r② ♥ ♦♥ ♣t s♦r♣t♦♥ ♦ ♥st♦rs♥ t tr♦♥♦ ♥trt♦♥ ♥ ♥t♦ t♦♥ P②s ttrs

❬❪ ♦♥ ♥ ♦ tr♦♥♦ ①tt♦♥s ♥ s♠♦♥t♦rs ♥♥st♦rs P②s tt

❬❪ ❱st ♥♥ ❱ ♥♦ P tts♥r ♥ ♦r② ♦ ts ♥ t ♥s♦tr♦♣② ♦ t tr♦♥ ♥r② ♦ss s♣tr♠ ♦tt♥♠ ♦① 2 P②s tt

❬❪ r♥♦♣♦♦s ♥♥ ♦ ♥ ❱st ♣t ♥ ♦sss♣tr ♦ r♦♥ ♥♥♦ts ♣♦r③t♦♥ ts ♥ ♥trt ♥trt♦♥s P②s tt

❬❪ ♦tt ❱st ♥♥ ❱ ♥♦ ♥ ♥r♥ ♥t♦

t♦♥ ♦ t tr t♥s♦r ♦ ss s♣rtts P②s

tt

❬❪ ♦tt ♠♠♣r ♥ ♥t♦ t♦♥s ♦ ♦♣t ♣r♦♣rts ♥

s♠♦♥t♦r s♣rtts P tss ❯♥rstà P t

❬❪ ♦tt ❱st ♥♥ ❱ ♥♦ ♥ ♥r♥ ♥t♦ ♥s♠♠♣r tr rs♣♦♥s ♦ s♣rtts P②s

❬❪ s t ❱st P♣♣ r♥ r ②♥t ♥ ♥♥ tr♦♥ strtr ♥ tr♦♥ ♥r②♦ss s♣tr♦s♦♣② ♦❩r2 ③r♦♥ P②s

❬❪ ♦tt r♥ r♥♦♣♦♦s s ♦tt ❱ ♥♦ ❱st ♦ ♥ ♥♥ r♦♠ ♠♦s t♦ s♦s tr♦ ♦ ♦♥r♥ ♥trt♦♥s ♥t ♥t ♠

❬❪ s ♥ r♥ ❱r♥ r♥té t ❱st ♥ ♥♥ tr♦♥ ①tt♦♥s ♥t♦ t♦♥s ♦ tr♦♥ s♣tr ♥♣♣t♦♥ t♦ ③r♦♥ ❩r2 tt♥ 2 ♥ ♣r♦s ♦① 2 ♦♠♣

t

❬❪ ♥ r ♥ ♦t♥ tr♦♥ s♦♥sst♥t❲ ♣♣r♦①♠t♦♥ ♣♣t♦♥ t♦ ♥ ♥ P②s tt

❬❪ r♥ ♥ t ♦rrét♦♥ ♥s trtr tr♦♥q s

♦s ♠ à ①② r① ♣♣r♦①♠t♦♥ ❲ t àP tss ♦ P♦②t♥q Ps r♥

Page 25: Some ab initio tudies of the physical properties of materials

P ❯ ❳

❬❪ ♥ r♥ t ❱st ♥♥ ③qr♦ r♦tt ♥ rrtt ①♥ ♥ ♦rrt♦♥ ts ♥ tr♦♥ ①tt♦♥ ♦ 2P②s tt ♥ rrr♥s r♥

❬❪ ♥ r♥ t ❱st ♥ ♥♥ t ♦ s♦♥sst♥②♦♥ qs♣rts ♥ s♦s P②s

❬❪ st ❱ ②tr ♥ ❱st ♥tr② sttr♥ ♥ s

♥t♦ t♦♥ ♦ t t ♣r♠trs ♦r ♦♥t r♦ s♠t♦♥s♣♣ P②ss

❬❪ st ❱ ②tr ♥ ❱st ♠♣ ♥t♦ st② ♦ Γ − X ♥tr② sttr♥ ♥ s ♥r ♣rssr P②s

❬❪ ❱st Pr♦♣rétés rt♦♥♥s ♦r α t rr ♦r 4 Ptss ❯♥rsté Prs ❱ r♥

❬❪ t ❱st Pr♦♣rétés rt♦♥♥s ♦r α t rr ♦r4 ès ♦t♦rt ❯♥rsté Prs ❱ r♥ t r♣♣♦rt

❬❪ ♥r ♠♥ ♥ ♦rt s♥♥ s♣rr ♠trs♥s

❬❪ ❱st r♦♥ ❩ér ss♦♥ P♦♥ r♥ ♥ r♠st tt②♥♠s ♦ α♦r♦♥ r♦♠ ♥t♦ t♦♥ ♥♠♥ sttr♥ ♥r ♣rssr P②s tt ♦

❬❪ ❱st r♦♥ ❩ér ss♦♥ P♦♥ r♠st ♥ r♥ tt ②♥♠s ♦ ♦sr α♦r♦♥ ♥r ♣rssr P②s tt

❬❪ ③③r ❱st ss♦♥ r♦♥ ♥ ♥r ♦rs♦ trtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr 4 ♦r♦♥ r P②s

tt

❬❪ ③③r ❱st ss♦♥ r♦♥ ♥ ♥r ♦rs♦ rrt♠strtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr 4 ♦r♦♥ r P②s tt

❬❪ ❱st ss♦♥ r♦♥ ♥ ♦rs♦ t♦♠ strtr ♥rt♦♥ ♣r♦♣rts ♦ ♦sr α♦r♦♥ ♥ 4 ♦r♦♥ r ♦♠♣

t

❬❪ ♥♥ ❲ ② ♥ ♦ P②s tt s réstts ♣♣r s♦♥t rr♦♥és ♦r♠ rr ♦r12 st qs ♥①st♥t s♦♥ ♥♦s s

❬❪ r ❱st ♥ Pr t♦♠ strtr ♦ ♦sr 4♦r♦♥ r r♦♠ rst♣r♥♣s ♥②ss ♦ s♣tr P②s

tt

Page 26: Some ab initio tudies of the physical properties of materials

P ❯ ❳

❬❪ r♠ts ❱ ❱ tr③♥ ♦ ♥ ♠② ♥

❬❪ ♥♦ ♥ ❨ tt ❲ ss ❩ ❨ r② ♥ ❱ ♦♦③♥♦ tr

❬❪ ♥ ♥ ❩ strtr ♦t♦♥ ♦ ♦r♦♥ r ♥t♦ t♦♥s ♣♣ P②s tt

❬❪ s♦ r ♥ t②♠❨♦s P②s

❬❪ ③ r③ ♥ ❨♦s♦♥ P②s tt

❬❪ ❱st st ♥ tr♥♥② ♦r♦♥ rs r♦♠ rst ♣r♥♣s♦r♥ ♦ P②ss ♦♥r♥ ♣r♦♥s rt t rrs ♦ ♣s

❬❪ ❱♦r ❲ ♥rt ♥ s ②♥♠ ♦r ♦♦r♦♥ r ♣♣ P②s

❬❪ ♥ ❲ ② ♥ ♠r ♦♥ ♦③ ♠♦r♣③t♦♥ ♥ ♦r♦♥ r ♥

❬❪ ♦s s ♥ ❨ ❨♣ tr♥♥ ♦r♠t♦♥♦ r♦♥ ♥ ♦r♦♥ strs ♥ ♦r♦♥ r r♥ ②♥♠ ♥♥tt♦♥♣♣ P②ss ttrs

❬❪ ❳ ❨♥ ❩ ♥ ❩♥ ♦ ♥ ❨ ❩♥ ♦t♦ ② ♥ ❲ ♥ ♣rssr③t♦♥ ♠♦r♣③t♦♥ ♦ s♥r②st♦r♦♥ r P②s tt

❬❪ ❳ ❨♥ ❲ ♥ ❲ ♥ ♠♥ s♣tr♦s♦♣② ♦ ♣rssr♥ ♠♦r♣♦s ♦r♦♥ r ♣♣ P②s tt

❬❪ ❱ r♥té t té♦rq s ♣ss tt♥ P tss ♦ P♦②t♥q Ps r♥

❬❪ r r ♥ t②♠❨♦s ❱♥ ♦♥tr♦ ♦ αr♦♠♦r ♦r♦♥ ② tr♦♥ ♦♣♥ P②s ♦♥ ttr

❬❪ P ❯♠r t♥t ♥ r♦♥ r♥ t s③ ♣ t♥ ♥st②♥t♦♥ ♥ ♠♥②♦② ♣rtrt♦♥ t♦r② ♦♥♠t

❬❪ ♠♥♥ ♥ ❱♥rt P②s

❬❪ ❲r tt r ♥ r♦♥ ♥t ♣♣r♦t♦ t♠♣♥♥t ♥st②♥t♦♥ ♣rtrt♦♥ t♦r② ♦r ♦♣t s♣tr♦s♦♣② P②s tt

❬❪ r r ♥ r ♥st② ♥t♦♥ t♦r② ♦ t tr♦♥tt② ♦ ♠♦r s P②s tt

Page 27: Some ab initio tudies of the physical properties of materials
Page 28: Some ab initio tudies of the physical properties of materials

♣tr

② q♥tt② t ♥rs ♦t ♠r♦s♦♣ tr♥t♦♥

♥ ts ♣tr sr t t♦rt ss s♥ ♥ t ♦♦♥ ♣trs

❲♥ sr♥ t rs♣♦♥s t♦ ♥ ①tt♦♥ t ♣♣ ♠r♦s♦♣ ♥ t t♦t ♦♥ t ♠r♦s♦♣ s r ♥♦t q ♠r♦s♦♣ r♣② rs ♦r t ♥t ♥ t st♥r ♥t♦♥ ♦t tr ♦♥st♥t ǫ t tstr rs♣♦♥s t ♠r♦s♦♣ ♦♥ssts ♦ t ♣♣ ♣♦t♥t δVbare ♥ ♦ t rtr ♣♦t♥tδVHartree tt ♦♠s r♦♠ t r ♥st② ♥ ② t ①tr♥ rtr ♥s t s♦ ♦ s tr♠♥s t♣♦r③t♦♥ ♦ t tr♦♥ s②st♠ ❬❪

♥st s♥ t tr♦♥tr♦♥ tr ♦♥st♥t ǫ ♥ t♦♦♥ st♦♥s ①♣t t ♥ ♦♥ ♥ t ♠r♦s♦♣ s t♦♥♠ t ♣♦t♥t ♦♥t♥s ♥ t♦♥ tr♠ t rs♣t t♦ ♦ ♥t♦♥ t ①♥ ♥ ♦rrt♦♥ ♣♦t♥t

♥r rs♣♦♥s ②s t♦ rst ♦rr t rt♦♥ t♥ t ①tr♥♣♣ ♣rtr♥ ♣♦t♥t δVbare ♥ t t♦t ♣♦t♥t δV t t ♠r♦s♦♣ s ♥rs ♦ t ♠r♦s♦♣ tr ♥t♦♥ ǫ−1 s♦♥♦♥ s t sr♥♥ ♥t♦♥ s t ② q♥tt② ♥♥ δVbare ♥ δV❬❪

δV (r, r′, t) =

ǫ−1(r, r′, t)δVbare(r′, t)dr′.

♥ t ♦♦♥ st♦♥s st♣ ② st♣ r qt♦♥ ♥ s♦♦ t ♥rs tr ♥t♦♥ s t ♥ t ♦♠♣tr ♣r♦r♠ s ♥ s t♦ ♦t♥ t rsts ♦ t ♥①t ♣trs

Page 29: Some ab initio tudies of the physical properties of materials

P ❨ ❯❨ ❱

P ❯

r♦♥ stt

t H (0) t ♣r♦ ♥ s♣ ♥♣rtr ♠t♦♥♥ ♥

H (0)|ψ(0)nk >= ε

(0)nk |ψ

(0)nk >,

r ε(0) ♥ ψ(0) r ♥s ♥ ♥t♦rs ♦ H (0) tt ♥ ♥① n ♥ t r♦♥ ③♦♥ t♦r k

♠t♦♥♥ ♦ qt♦♥ ♥ sr ♠♥②♦ s②st♠♦r s♠♣② ♥ ♠t♦♥♥ ♦r s♥ ♣rt ♥ t ttr s ♦♥♦t♥ ①♣rsss H (0) ♥ t r♠♦r ♦ ♥st② ♥t♦♥ t♦r② ❬ ❪r t ♦♥ssts rs♣t② ♦ t ♥t ♦♣rt♦r t tr♦♥♦♥ ♣♦t♥t VIe ♥ t s♦♥sst♥t ♣♦t♥t

H (0) =−~

2

2m∇2 + VIe + Vscf ,

r ~ s P♥s ♦♥st♥t ② π ♥ m t tr♦♥ ♠ssVIe s ♦t♥ trt ♥ t ♣s♦♣♦t♥t ♣♣r♦①♠t♦♥ ❬❪ ♥ Vscf

♦♥ssts ♦ t ss tr♦stt ♣♦t♥t VHartree ♥ t q♥t♠ ①♥ ♥ ♦rrt♦♥ ♣♦t♥t Vxc

♥ t s♥ ♦ ♥② ♣rtrt♦♥ t t♠ ♣r♦♣t♦♥ ♦ t tr♦♥ ♥t♦♥ s ♥ ②

|φ(0)nk (t) >= e−iε

(0)nk

t~ |ψ

(0)nk > .

♥ t st ♦ |φ(0)(t) > ♦r♠s ss ♦ stt♦♥r② stts ♦r t ♥♣rtr s②st♠ ❬❪

t ♦ ♣rtrt♦♥

tr♦♥ ①tt♦♥s r t♠ ♣♥♥t ♣r♦sss ♦♦♥ ❬❪t♦tr t t ♥tr♦t♦♥ ♦ t♠ ♣♥♥t ♣rtrt♦♥ δV (t)♦♥srt♦♥ ♦ t♦t ♥r② rs ♦♥ ♥ tr r ♥♦ ♦♥r ♥② stt♦♥r② stts s②st♠ ♥ ♠ tr♥st♦♥ r♦♠ t ♥t stt♦♥r②stt |ψ

(0)nk > t♦ ♥② ♦tr stt

tr♥st♦♥ ♣r♦t② ♠t t ♥ sr ss ❬❪ ♦r♥st♥ t ♣rtrt♦♥ s ♣♣ t② ♥ t ♥t stt|ψ

(0)nk > s ♥♦♥ ♥rt stt♦♥r② stt t s②st♠ ♠② r♠♥ ♥ ts

stt ♥♦tr ①tr♠ s s t ♣♣t♦♥ ♦ δV (t) ♥ r② s♦rtt♠ t s②st♠ s ♥♦ t♠ t♦ ♥ ♥ ♠t st② ♥ t stt |ψ(0)

nk > ♦r s ♥♦ ♦♥r stt♦♥r② stt ♦ t ♥ ♠t♦♥♥

Page 30: Some ab initio tudies of the physical properties of materials

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t s δV (r, t) t t♦t t♠ ♣♥♥t ♣rtrt♦♥ ♦♥sst♥♦ t ①tr♥ ♣♣ ♣♦t♥t δVbare ♣s t tr♦♥ rs♣♦♥s δVscf ❲t♥ t ♥st② ♥t♦♥ t♦r② t ttr ♦♥ssts ♦ t rt♦♥ ♦t tr♦stt ♣♦t♥t δVHartree ♣s t rt♦♥ ♦ t ①♥ ♥♦rrt♦♥ ♣♦t♥t δVxc

δV (r, t) = δVbare(r, t) + δVHartree(r, t) + δVxc(r, t).

t♦t ♠t♦♥♥ s H(t) = H (0) + δV (t) ♥ t♦ t t♣r♦♣rts ♦ t ①t stt ♦♥ s t♦ s♦ rö♥rs qt♦♥

i~d |ψ(t)

dt= H(t)|ψ(t) > .

♥ ♦♥ s t♦ t t ♥t♦♥s ♥ t ss ♦ t stt♦♥r② stts ♦ t ♥♣rtr s②st♠ ♥ ② q ❬❪

|ψ(t) >=∑

nk

anke−iε

(0)nk

t~ |ψ

(0)nk > .

♠ ♣♥♥t ♣rtrt♦♥ t♦r②

♣♥ t ank ♦♥ts t♦ rst♦rr t ♥t♦♥ rs

|ψ(t) >=∑

nk

a(0)nk e−iε

(0)nk

t~ |ψ

(0)nk > +

nk

a(1)nk (t)e−iε

(0)nk

t~ |ψ

(0)nk > + ...

s♦t♦♥ ♦ q t♦ ③r♦th ♦rr rsts ♥ t ③r♦t♦rr a(0)nk

♥ t♠♥♣♥♥t

♥ s t t q t♦ rst♦rr

i~∑

nk

da(1)nk (t)

dte−iε

(0)nk

t~ |ψ

(0)nk >=

nk

a(0)nk e−iε

(0)nk

t~ δV (t)|ψ

(0)nk > .

Pr♦t♥ ♦♥t♦ < ψ(0)mk′| ♦♥ ♦t♥s

a(1)mk′(t) =

−i

~

nk

a(0)nk

∫ t

t0=0

e−i(ε(0)nk

−ε(0)

mk′) τ

~ < ψ(0)mk′|δV (τ)|ψ

(0)nk > dτ .

❲ ♥♦ ♦♠♣t t ♥tr ♥ q ♦r ♥ ♦r♠ ♦ t♣rtr♥ ♣♦t♥t

Page 31: Some ab initio tudies of the physical properties of materials

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♦t♦♥ ♦r t♠ ♣r♦ ♣rtrt♦♥

♦♦♥ ❬❪ t s s♣♣♦s tt t ♣♣ ♣rtrt♦♥ s r♠t♥♥ t♠ ♣r♦

δVbare(r, t) = (δVbareeiωt + c .c .)eαt ,

r t tr♠ eαt s ♥rst♦♦ t r ♣♦st ♥ s♠ α r♥ts ♥ t st ♦♥ ♦ t ♣rtrt♦♥ rst tr♠ ♦♥t rt♥ s st♥s ♦r ♣♦t♦♥ ♠ss♦♥ ♥ c .c . st♥s ♦r t♦♠♣① ♦♥t tr♠ ♣♦t♦♥ s♦r♣t♦♥

t s ♠♦r♦r s♣♣♦s tt t ♣♣ ♣rtrt♦♥ s ♥ s♣s♦② r②♥ ①tr♥ ♣♦t♥t ❬❪

δVbare(r, t) = δVbare(q, r,ω)e−i(q.r−ωt)eαt + c .c .,

r t ♥t ♦ t ♣rtrt♦♥ s 2π/|q| ♥ t t♦r♥t |q| s s♠ ♦♠♣r t♦ t r♣r♦ tt t♦r ♥t |G|

t♥ ♠♠♦r② ts t t♦t ♣♦t♥t s t♦ rst ♦rr s♦ t♠♣r♦

δV (t) = (Fe iωt + F †e−iωt)eαt .

❲t F = F q = F 0(q, r,ω)e−i(q.r) q rs

δV (r, t) = [F 0(q, r,ω)e−i(q.r−ωt) + F 0 †(q, r,ω)e i(q.r−ωt)]eαt .

♥ ①♣rsss F 0 ♥ tr♠s ♦ ts ♦rr ♦♠♣♦♥♥ts ♥ t s♣s t♦ r ♥ t

X (r, t) =

dω∑

G

X (G,ω)e−iG.re iωt

s ♦ ♦ s t t♦t ♣♦t♥t ♥ ♥r ♦♥t♥ r♣②r②♥ tr♠s t t♦r q + G

δV (r, t) =∑

G

[F 0(q,ω,G)e−i(q+G).r+iωt) + F 0 ∗(q,ω,G)e i(q+G).r−iωt)]eαt .

t s

Fqmk′nk(t) = (e iωt < ψ

(0)mk′|F

q|ψ(0)nk >

ε(0)nk − ε

(0)mk′ − ~ω − i~α

+ e−iωt < ψ(0)mk′|F

q †|ψ(0)nk >

ε(0)nk − ε

(0)mk′ + ~ω − i~α

)eαt .

♦t♦♥ ♦ q ②s

aq (1)mk′ (t) =

nk

a(0)nk [e−i(ε

(0)nk

−ε(0)

mk′) t

~ Fqmk′nk(t) −Fq

mk′nk(t0 = 0)],

Page 32: Some ab initio tudies of the physical properties of materials

P ❨ ❯❨ ❱ P ❯

♥ ts

|ψq(t) >=∑

nk

a(0)nk e−iε

(0)nk

t~ |ψ

(0)nk > +

nkmk′

a(0)mk′(t)[e

−iε(0)

mk′t~ Fq

nkmk′(t) − e−iε(0)nk

t~ Fq

nkmk′(t0 = 0)]|ψ(0)nk

❩r♦th ♦rr ♥st② ♠tr①

s♥ ♣rt ♥st② ♠tr① rs

ρq(t) = |ψq(t) >< ψq(t)|.

♦ ③r♦th ♦rr ♦♥ s t |ψq(t) > r♦♠ q

ρ(0) =∑

nkmk′

a(0) ∗mk′ a

(0)nk e−i(ε

(0)nk

−ε(0)

mk′) t

~ |ψ(0)nk >< ψ

(0)mk′|,

t ❬❪

ρ(0)|ψ(0)pk” >= f (0)(ε

(0)pk”)|ψ

(0)pk” >=

nk

a(0) ∗pk” a

(0)nk e−i(ε

(0)nk

−ε(0)pk”)

t~ |ψ

(0)nk >,

r f (0)(ε(0)pk”) st♥s ♦r t ♦♣t♦♥ ♥♠r ♥ s

< ψ(0)lk1|ρ(0)|ψ

(0)pk2

>= f (0)(ε(0)pk2

)δlk1;pk2,

♦♥ ts t r② ♠♣♦rt♥t rt♦♥

a(0) ∗pk2

a(0)lk1

e−i(ε

(0)lk1

−ε(0)pk2

) t~ = f (0)(ε

(0)pk2

)δlk1;pk2.

q s ♥ t ♥①t st♦♥

rst ♦rr ♥st② ♠tr①

♥ ♦t♥s t rst ♦rr ♥st② ♠tr① r♦♠ qs ♥

ρq (1) =∑

nkmk′pk”

a(0) ∗mk′ a

(0)pk”[e

−i(ε(0)pk”−ε

(0)

mk′) t

~ Fqnkpk”(t)−

e−i(ε(0)nk

−ε(0)

mk′) t

~ Fqnkpk”(t0 = 0)]|ψ

(0)nk >< ψ

(0)mk′| + c .c .

♠tr① ♠♥ts t♥ r s♥ q

< ψ(0)lk1|ρq (1)|ψ

(0)pk2

> =

f (0)(ε(0)pk2

)[Fqlk1pk2

(t) − e−i(ε

(0)lk1

−ε(0)pk2

) t~ Fq

lk1pk2(t0 = 0)]+

f (0)(ε(0)lk1

)[Fq ∗pk2lk1

(t) − e−i(ε

(0)lk1

−ε(0)pk2

) t~ Fq

pk2lk1(t0 = 0)].

Page 33: Some ab initio tudies of the physical properties of materials

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♠♠r♥ q δV q(r, t) = (F qe iωt + F q †e−iωt)eαt t ♠tr①♠♥ts ♥ tr♠s ♦ F q ♥ F q † ♦♣rt♦rs r

< ψ(0)lk1|ρq(1)|ψ

(0)pk2

>= eαt Iq0 +

eαte iωt [f (0)(ε(0)pk2

) − f (0)(ε(0)lk1

)]< ψ

(0)lk1|F q|ψ

(0)pk2

>

ε(0)pk2

− ε(0)lk1

− ~ω − i~α+

eαte−iωt [f (0)(ε(0)pk2

) − f (0)(ε(0)lk1

)]< ψ

(0)lk1|F q †|ψ

(0)pk2

>

ε(0)pk2

− ε(0)lk1

+ ~ω − i~α.

♥ t ♣r♦s qt♦♥ t Iq0 tr♠ ♥ ♦s♥ s tt t ♥t

t♠ t0 rst ♦rr tr♠s ♥ t ♥t♦♥ ♥ ♥ t ♥st② ♥saq (1)nk (t0 = 0) = 0 ♥ ρq (1)(t0 = 0) = 0

Iq0 = −e

−i(ε(0)lk1

−ε(0)pk2

) t~ [f (0)(ε

(0)pk2

) − f (0)(ε(0)lk1

)]

(< ψ

(0)lk1|F q|ψ

(0)pk2

>

ε(0)pk2

− ε(0)lk1

− ~ω − i~α+

< ψ(0)lk1|F q †|ψ

(0)pk2

>

ε(0)pk2

− ε(0)lk1

+ ~ω − i~α).

tr♥t② ♦♥ ss t t st t t0 = −∞ eαt → 0♥ t♥ t ♥t ♦♥t♦♥s ①♣rss ② I

q0 ♥s

♠tr① ♠♥ts ♦ t rst ♦rr ♥st② ♠tr① ♥ q r② q♥tts t♦ ♦t♥ t tr♦♥ rs♣♦♥s ♥t♦♥s χ0 χ ♥ ǫ−1 ♦♦t♥ t♠ ♥r③ rö♥rs qt♦♥ ♥ t ♥♠♥r s♣♦♥s ♥ t♦ ts t♦rt r♠♦r

♦♥srt♦♥ ♦ r②st ♠♦♠♥t♠

♥ ♦ qt♦♥s ♠tr① ♠♥ts ♦ t ♦r♠ < ψ(0)lk1|F q|ψ

(0)pk2

> r∑

G

F 0(G,q,ω)∑

G1

ψ(0)pk2

(G1)∑

G2

ψ(0) ∗lk1

(G2)

dre−i(q+G).re−i(k1+G1).re i(k2+G2).r.

♥tr ②s t t ♥t♦♥

δ(k2 + G2 − k1 − G1 − q − G),

♥ ts t ♦r t ♦♥srt♦♥ ♦ t r②st ♠♦♠♥t♠

k2 = k1 + q + G,

r G s r♣r♦ tt t♦r ❯♠♣♣ ♣r♦sss r ♥♥ t s♠ G 6= 0 ② rs t♦ ♦ ♦rrt♦♥s ❬❪

r♦♠ ♥♦ ♦♥ k2 s ss♠ t♦ sts② t ♦ ♦♥srt♦♥ q

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P ❨ ❯❨ ❱ P ❯

♥ ♥ ♥ t tr♦♥ ♥st②

♥ ♥ ♥ t tr♦♥ ♥st② δnq(r, t) s t ♦♥ tr♠♦ t rst♦rr ♥st② ♠tr① ♥ rs

(−e)δnq(r, t) = Tr [ρq (1)(−e)δ(r − r)],

r r s t ♣♦st♦♥ ♦♣rt♦r ♥ −e s t r ♦ ♦♥ tr♦♥♦♣♥ ♣r♦s qt♦♥ ♦♥ t ss ♦ t ♥♣rtr ♥

t♦♥s ♦sr rt♦♥ ②s

δnq(r) =< r|ρq (1)|r >

=∑

lk1pk2

< r|ψ(0)lk1>< ψ

(0)lk1|ρq (1)|ψ

(0)pk2

>< ψ(0)pk2

|r >

=∑

lk1pk2

ψ(0) ∗pk2

(r) < ψ(0)lk1|ρq (1)|ψ

(0)pk2

> ψ(0)lk1

(r).

δnq s t ♦r♠

δnq(r, t) = δn0 + δnq(r)e iωteαt + δnq†(r)e−iωteαt ,

r δn0 rsδn0 =

lk1pk2

ψ(0) ∗pk2

(r)ψ(0)lk1

(r)eαt I 0q ,

♥ ♥ss ♥ t t ♣♣r♦①♠t♦♥

♥ qt♦♥ δnq(r) rs

δnq(r) =∑

lk1pk2

ψ(0) ∗pk2

(r)ψ(0)lk1

(r)[f (0)(ε(0)pk2

) − f (0)(ε(0)lk1

)]< ψ

(0)lk1|F q|ψ

(0)pk2

>

ε(0)pk2

− ε(0)lk1

− ~ω − i~α

P♦ss♦♥s qt♦♥

♥ t♦♥ P♦ss♦♥s qt♦♥ ♥s t tr♦♥ ♥st② t♦ t ♣♥♦ t tr♦stt ♣♦t♥t ❬❪ ①♣♥ t♦ t rst ♦rr t ♥s t♥ ♥ ♥ t tr♦♥ ♥st② t♦ t ♣♥ ♦ t ♥ ♥t tr♦stt ♣♦t♥t δV q

Hartree

∇2r δV

qHartree(r, t) = −4πe2δnq(r, t).

♦rr tr♥s♦r♠t♦♥ ♦ t rtr ♣♦t♥t ②s t ♦♦♥ qt♦♥ r♠♠r♥ tt t ♥ ♣♦t♥t ♦♥t♥s tr♠s t t♦r q + G ♦ s

δV qHartree = (F q

Hartreeeiωt + c .c)eαt ,

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FqHartree =

G

F 0Hartree(q,G,ω)e−i(q+G).r,

♦rr tr♥s♦r♠ ♦ t qt♦♥ rs

δnq(r) =∑

G

δn(q + G,ω)e−i(q+G).r.

♥ t t ♣♣r♦①♠t♦♥ ♦♥ ♦t♥s t rt♦♥s♣ t♥t ♦rr ♦♠♣♦♥♥ts ♦ t rtr ♣♦t♥t ♥ ♦ t ♥st② s

F 0Hartree(q,G,ω)|q + G|2 = 4πe2 δn(q + G,ω).

♦r ♥② G ♦♠♣♦♥♥t ♦tr t♥ G = 0 ♦♥ s

δn(q + G,ω) = F 0Hartree(q,G,ω)

|q + G|2

4πe2.

♦r ♦♥ ♥t q = 0 ♣rtrt♦♥ ♥ G = 0 δn(q+G,ω) = 0♥ ♦tr ♦rs t ♥ ♥ ♥ ♥st② s ♥♦ ♠r♦s♦♣ ♦♠♣♦♥♥t t t♦t ♠r♦s♦♣ tr♦♥ ♥st② s ♣t ♦♥st♥t ♥ t①t stt

s♣♦♥s ♥t♦♥ χ0

♣♥ ♥ q t ♠tr① ♠♥ts ♦ ρq (1) t q ♥♥♥ I 0 ♥ χ0 s

δn(q + G,ω) =∑

G′

F 0(q,G′,ω)χ0(q + G,q + G′,ω)+

G′

F 0 ∗(q,G′,ω)χ0(q + G,−q − G′,−ω)

+∑

G′

F 0(q,G′,ω)I 0(q + G,q + G′,ω) +∑

G′

F 0 ∗(q,G′,ω)I 0(q + G,−q − G′,−ω),

♦♥ ♦t♥s t I 0 tr♠ ♦s t ♥ss ♥ t t ♠tt0 = −∞

I 0(q + G,q + G′,ω) = −∑

lk1pk2

e−i(ε

(0)lk1

−ε(0)pk2

) t~ [f (0)(ε

(0)pk2

) − f (0)(ε(0)lk1

)]

< ψ(0)lk1|e i(q+G).r|ψ

(0)pk2

>< ψ(0)pk2

|e−i(q+G′).r|ψ(0)lk1>

ε(0)pk2

− ε(0)lk1

− ~ω − i~α.

tr♦♥ rs♣♦♥s ♥t♦♥ χ0 rs

Page 36: Some ab initio tudies of the physical properties of materials

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χ0(q + G,q + G′,ω) =

lk1pk2

[f (0)(ε(0)pk2

) − f (0)(ε(0)lk1

)]< ψ

(0)lk1|e i(q+G).r|ψ

(0)pk2

>< ψ(0)pk2

|e−i(q+G′).r|ψ(0)lk1>

ε(0)pk2

− ε(0)lk1

− ~ω − i~α.

tr♦♥ rs♣♦♥s ♥t♦♥ χ0 ♥s t rt♦♥ ♦ t tr♦♥r ♥st② t♦ t t♦t ♣♦t♥t tr♦ qt♦♥

s♣♦♥s ♥t♦♥ χ

♦ ♦t♥ t rt♦♥ t♥ t rt♦♥ ♦ t tr♦♥ r ♥st②♥ t ①tr♥ ♣♦t♥t ♦♥ ♦♦s ♦r t rs♣♦♥s ♥t♦♥ χ s s

δn(q + G,ω) =∑

G′

δVbare(q,G′,ω)χ(q + G,q + G′,ω)+

G′

δV ∗bare(q,G′,ω)χ(q + G,−q − G′,−ω)

+∑

G′

δVbare(q,G′,ω)I (q + G,q + G′,ω) +∑

G′

δV ∗bare(q,G′,ω)I (q + G,−q − G′,−ω),

r ♦r♥ t♦ q t ①tr♥ ♣♦t♥t ♦s ♥♦t r② ♦r ♥t s♦ tt

δVbare(q,G,ω) = δ(G, 0)δVbare(q,ω).

♦rr tr♥s♦r♠♥ qt♦♥ ♦♥ s

F 0(q,G,ω) = δVbare(q,G,ω) + F 0Hartree(q,G,q,ω) + F 0

xc(q,G,ω),

r F 0Hartree s ♥ ♥ ♥ rt♦♥ ♦ t ①♥ ♥

♦rrt♦♥ ♣♦t♥t δVxc [δn(G)] s♦ ♣♥s ♦♥ t rt♦♥ ♦ t tr♦♥ ♥st②

♥ ♥ t s♠♣st ♣♣r♦①♠t♦♥ t ①♥ ♥ ♦rrt♦♥ ♣♦t♥t s t♥ t♦ ♦♦ t t♠ ♣♥♥ ♦ t ♥st② ♦r ♥st♥ t♥ t ♦ ♥st② ♣♣r♦①♠t♦♥ t ♥r③ r♥t♣♣r♦①♠t♦♥❬❪ ♦r t t ♦ ♥st② ♣♣r♦①♠t♦♥❬❪ t ①♥ ♥ ♦rrt♦♥ r♥ fxc s ♥ s

fxc(r, t) =δVxc(r, t)

δn(r′, t′)δ(r − r′)δ(t − t ′)

Page 37: Some ab initio tudies of the physical properties of materials

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s♦ ttδVxc(r, t) = fxc(r, t)δn(r, t).

♥ t ♦ s♠♣st ♣♣r♦①♠t♦♥s t r♥ s ♦s♥ t♦ ♦ ♥s♣ ♥ t♠

❯s♥ ♦ ♥t♦♥ t♦tr t q ♦♥ ♦t♥s tt

F 0(q,Gω) = δVbare(q,G,ω)+∑

G′

[4πe2

|q + G′|2δ(G′−G)+fxc(G

′−G)]δn(q+G′,ω).

❲ ♥♦ ♠ qs ♥ q ♥ t t ♣ ♦ q ♦t♥ t tr♠ ♥ t ♥t ♦♥t♦♥s ♥ss ♥ tt ♠t

I (q + G,q + G′,ω) = I 0(q + G,q + G′,ω)+

I 0(q + G,q + G′,ω)∑

G”

[4πe2

|q + G”|2δ(G′ − G”) + fxc(G

′ − G”)]χ(q + G′,q + G”,ω).

♦r t rs♣♦♥s ♥t♦♥ χ ♦♥ s t t ②s♦♥ qt♦♥ ❬❪

χ(q + G,q + G′,ω) = χ0(q + G,q + G′,ω)+

χ0(q + G,q + G′,ω)∑

G”

[4πe2

|q + G”|2δ(G′ − G”) + fxc(G

′ − G”)]χ(q + G′,q + G”,ω).

t♦♥ ♦ t rs♣♦♥s ♥t♦♥ χ rqrs ♦t t ♥♦ ♦t rs♣♦♥s ♥t♦♥ χ0 q ♥ ♦ t ①♥ ♥ ♦rrt♦♥r♥ fxc q

♥rs tr ♥t♦♥ ǫ−1

♦ ♦t♥ t rt♦♥ t♥ t ①tr♥ ♣♦t♥t δVbare ♥ t t♦t♣♦t♥t δV ♦♥ ss t t qs ♥ tt

δn(q + G,ω) =∑

G′

δVbare(G′,q,ω)χ(q + G,q + G′,ω),

s♦ tt qt♦♥ rs

F 0(q,G,ω)) =∑

G′

δVbare(q,G′,ω)δ(G − G′)+

G”

[4πe2

|q + G”|2δ(G − G”) + fxc(G − G”)]χ(q + G”,q + G′,ω).

Page 38: Some ab initio tudies of the physical properties of materials

P ❨ ❯❨ ❱ P ❯

♥rs tr ♥t♦♥ ǫ−1 s t ② q♥tt②

ǫ−1(q + G,q + G′,ω) = δ(G − G′)+∑

G”

[4πe2

|q + G”|2δ(G − G”) + fxc(G − G”)]χ(q + G”,q + G′,ω),

r q s t t♦r ♦r ♠♦♠♥t♠ tr♥sr t♥ t rst r♦♥③♦♥

ǫ−1 ♥s ♦♥ t ♠r♦s♦♣ s t ①tr♥ ♣♦t♥t t♦ t t♦t♣♦t♥t ♥s t r②st

F 0(q,G,ω) =∑

G′

δVbare(q,G′,ω)ǫ−1(q + G,q + G′,ω).

♥r rs♣♦♥s ♥ r s♣

♥ r s♣ qt♦♥s ♦ ♥r rs♣♦♥s t♦r② r ❬❪

δVtot(r,ω) =

ǫ−1(r, r′,ω)Vbare(r′,ω)dr′.

δn(r,ω) =

χ0(r, r′,ω)δVtot(r′,ω)dr′,

δn(r,ω) =

χ(r, r′,ω)Vbare(r′,ω)dr′.

♥ ttr qt♦♥s ♠♠♦r② ts ♥ t♠ r ♦♠ttχ0 rs

χ0(r, r′,ω) =

i ,j

(fi − fj)ψi(r)ψ

∗j (r)ψj(r

′)ψ∗i (r

′)

ωij − ω − i~α,

r i ♥ j r ♦ ♥①s ♦r t ♥ ♥♠r ♥ r②st t♦r ♥ ωij = εi − εj

r tr ♥t♦♥ ② tr♦♥

♥r②♦ss s♣tr♦s♦♣②

❲♥ r ♣rt ♦s t tr♦♥s ♥ t♦♠s t s r♥t② ♦r♥ t♦ ts ♠ss ts ♠ss s rr t♥ t tr♦♥ ♠ss ♦s♦♥ t tr♦♥s t♦ ♥r② ♦ss rs ♦s♦♥ tt♦♠s st t t♦♥ ♦ t trt♦r② t ♥♥t♣rt s ♥ tr♦♥ tr ♦t ♥st sttr♥ ♥ t♦♥

Page 39: Some ab initio tudies of the physical properties of materials

P ❨ ❯❨ ❱

P ❯

♦ t tr♦♥ ❬❪

♥ t t②♣ ♦ ①♣r♠♥t ♦♥sr r tr♥s♠ss♦♥ tr♦♥ ♥r②♦ss s♣tr♦s♦♣② ♥r② ♠ s tr♥s♠tt tr♦ t♥ s♠♣♥ ①♣r♥s ♦t st sttr♥ qsst sttr♥ t ①tt♦♥ ♦ ♣♦♥♦♥ ♦r ♥st sttr♥ r t ♦♦♠ ♦ t♥♥t tr♦♥ ♥trts t t tr♦♥s ♥ t s♦ ♥ s rs t♦♦♥t♥ ♦t ①tt♦♥s t ♣s♠♦♥s ❬❪

♥♥t tr♦♥ s r② ♦♥r♥ ♦♦♠♥ ♥trt♦♥r♦♠ t ♥ tr♦♥s ♦ t s♦ s ♥trt♦♥ s rs♣♦♥s ♦rt ♥r② ♦ss ♥ s ♥ s♦♥ t♦ t♦♦ ♦♥r♥ t♦ trt♥ ♣rtrt♦♥ t♦r② ❬❪ r♦r t t♦rt s♠ ♦r sr♥t r♦♠ t♦s ♦r ♣♦t♦♠ss♦♥ ♦r s♦r♣t♦♥ s♣tr

♦r♥ t♦ r ❬❪ s t ♥trt♦♥ ♥t s r② ♦♥ ♥trt t s♦ s ♦♠♦♥♦s ♠♠ ♥ r② ♦♥ tr trt♠♥t♦ ts ♦♥r♥ ♥trt♦♥s ♥ tt s t ♣♦t♥t rt ② ttr♦♥ ♠♦♥ t ♦♥st♥t ♦t② v s ♥ ② P♦ss♦♥s qt♦♥t r♥ t qt♦♥ t tr ♥t♦♥ ǫqav ♦ t ♠♠♦♥sr s ♦♠♦♥♦s s ♥♦ ♥srt ♥ ①s qt♦♥ ♦r ttr s♣♠♥t ②♥ ♦r P♦ss♦♥s qt♦♥

ǫav (t,q)∇2r V (r, t) = −4πe2nq(r, t),

r n = eδ(r − vt) s t r ♦ t ♥♥t tr♦♥ ♥ t ♦qt♦♥ t tr ♥t♦♥ s ♥ r ♦r r t♦ t r② ♦♥r♥ ♥tr ♦ t ♥trt♦♥ s ♠r♦s♦♣ q♥tt② s ♦r t♠♣♥♥t ♥ ♣♥s ♦♥ t rt♦♥ ♥ ♠♦ ♦ t tr♥srr ♠♦♠♥t♠ q

♦ r♥t ♥st sttr♥ r♦ss st♦♥ ♦r st tr♦♥srs

∂2σ

∂Ω∂ω= D

4πǫ0(eπa0)2

ℑ(−1

qǫavq)

r ǫav = ǫav (ω = Eloss, q) s t ♦♥ ♠♥t ♦ t ♥rs ♠r♦s♦♣ tr ♥t♦♥ D s t s♠♣ t♥ss a0 s t ♦r rs♥ q s t sttr♥ t♦r ℑ(ǫ−1

av ) s t ♦ss ♥t♦♥ tt ♣♥s ♦♥ t ♦ss ♦ ♥t ♥r② Eloss ♦ t tr♥s♠tt tr♦♥ ♠

rt♦♥s♣ t♥ t r ♥t♦♥ ǫav (ω,q) ♥ t ♠r♦s♦♣ ♥t♦♥ s

ǫav (ω,q) =1

ǫ−1(q + G,q + G′,ω)G=G′=0

,

Page 40: Some ab initio tudies of the physical properties of materials

P ❨ ❯❨ ❱ P ❯

r ǫ−1 s ♥♦ ♦r tstr rs♣♦♥s ♥ ② t st♥r ♥t♦♥ ♦ t ♠r♦s♦♣ tr ♥t♦♥

ǫ−1(q + G,q + G′,ω) = δ(G − G′) +4πe2

|q + G|2χ(q + G,q + G′,ω).

❲t rs♣t t♦ q ♦r t tr♦♥tr♦♥ tr ♥t♦♥♦♥② t tr♦stt ♣♦t♥t s ♥ ♥ ♥ q ♥ ts ♥ t♥ ♥t♦ ♦♥t tt ♥ s ♥ ①♣r♠♥t t ♣r♦ s ♥ tr♦♥ t r② ♥r② ♥ tt s ❱❱ tr♦♥tr♦♥①♥ ♥ ♥♦r ♥ r t t t ♦♦♠ r②st ♣♦t♥t♥ q ❬❪ tr♦♥tr♦♥ ①♥ s ♣♦ss ♦♥② ♥ t t♦tr♦♥s t s♠ ♥r② ❬❪

♥② ♦♥ ♥♦ts tt t tstr ♥t♦♥ ♦ q ♥ ttr♦♥tr♦♥ rs♣♦♥s ♦ q ♥ ♥♦t ♦♥ t r② ♥r②s t ①♥ ♥ ♦rrt♦♥ r♥ s ♥♦t rq♥②♣♥♥t ♥♥② t ♣♣r♦①♠t♦♥s

Page 41: Some ab initio tudies of the physical properties of materials
Page 42: Some ab initio tudies of the physical properties of materials

♣tr

♦rt rsts tr♦♥♥r② ♦ss s♣tr

♥tr♣rtt♦♥ ♥ ♣rt♦♥ ② t t♦r② ♦ tr♦♥ s♣tr ♦t♥ ② t ①tt♦♥ ♦ ♥ tr♦♥s ♥ d ♠t ♦①s s r②♠♣♦rt♥t st ♦♠♥♥ ♦t t t② ♦ t ①t stt tt ♥ ♦ ♣r♦♣r② sr♥ d ♠♥ts ♥ t s♠t♦♥ s s ♦r♠ ts ♥ ♦♥ s ♣rt t ♣r♦♠ ♦ str♦♥ tr♦♥♦rrt♦♥ s t ♦s ♦ t ②♥♠ ♠♥ t♦r② ❬❪

♥ t ♦♦s ♦♥♥trt ♦♥ ❩r2 ♥ 2 ♠trs ♥ t d s r ♥r② ♠♣t② s ♠trs r ♠♣♦rt♥t ♦r ♥r♣♣t♦♥s ❩r♦♥ s sr ♥ t ♣♣♥①

♥ ts ♦①s ♥♦ str♦♥ tr♦♥ ♦rrt♦♥s r ①♣t t♦ ♦rt s ♥♦♥tss ♥ ♠♣♦rt♥t ts t♦ ♥rst♥ ♠♦♥ t t♦rt♠t♦s r ♥ ♣tr ♦ t♦r② s ♣♣r♦♣rt ♦r ts♦①s

♥ ts ♣tr ①♣♥ tr♦ s♦♠ ①♠♣s ♦ sr♣t♦♥ s ♥ssr② ♦r tr♦♥ ♥r② ♦ss s♣tr ♦r ts ♥ rsts♥ ♦♥ ♥ ♠② ♦r♣② ❬ ❪ s♦ ①♣♥ ♥ s♦♠ tt r♥t strtrs ♣♣r ♥ t r ♥ ♠♥r② ♣rts ♦ ttr ♥t♦♥ tt ts ♥ ♥r♣r♥ts r ss♥t♥ r♥t ♦r ♠♥② tr♥st♦♥ ♠t ♦①s

♥♦♠ ♣s ♣♣r♦①♠t♦♥

♦r②

s s♥ ♥ t ♣r♦s ♣tr t ♣♦r③t② ♦r ♥♣♥♥t ♣rtsχ0 ♥ qt♦♥ ♥ rtt♥ t♦ rst ♦rr ♥ ♣rtrt♦♥ s s♠♦r ♥♣♥♥t tr♥st♦♥s t♥ ♥♣rtr stts ❲ t ♥st②

Page 43: Some ab initio tudies of the physical properties of materials

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❨ P

♥t♦♥ t♦r② s ♦r strt♥ ♣♦♥t ♦r t ♥♣rtr r♦♥ sttt ♥t♦♥s ψi ♥ s ♦ t tr♥st♦♥ ♥r② ωij = εi −εj ♥t r♥ t♥ t ♥s ♦r stts ψi ♥ ψj

χ0(q + G,q + G′,ω) =∑

i ,j

(fi − fj)< ψj |e

i(q+G).r|ψi >< ψi |e−i(q+G′).r′|ψj >

ωij − ω − i~α,

r t s♠ r♥s ♦r stts ♥ ♦♣t♦♥ ♥♠rs fi ,j rs♠r t♥ ♦r q t♦ ♥t②

♥ rst st♣ ♥t♥ ♦ ts ♥ ♣♣r♦①♠t♥ χ ② χ0t ♠r♦s♦♣ ♥rs tr ♥t♦♥ ♥ rt② t r♦♠χ0 s❬❪

ǫ−1RPA(q + G,q + G′,ω) = δ(G − G′) +

4πe2

|q + G|2χ0(q + G,q + G′,ω).

♦ qt♦♥ s t ♥♦♠ Ps ♣♣r♦①♠t♦♥ t♦t ♦ ts st♥r ♥t♦♥ ♦ t sr tr ♥t♦♥ s❬❪

ǫRPA(q + G,q + G′,ω) = δ(G − G′) −4πe2

|q + G|2χ0(q + G,q + G′,ω).

sts ♥ ③r♦♥

♥ r r♣♦rt t tr ♥t♦♥ ǫ ♦r ❩r2 t ♥t P t♦t ♦ s s ♥s t r ♣rt ǫ1 s s♦♥ ♥t t♦♣ ♣♥ t ♠♥r② ♣rt ǫ2 ♦rrs♣♦♥♥ t♦ t s♦r♣t♦♥ s♣tr♠ ♥ t ♥tr ♣♥ ♥ ♥ t ♦tt♦♠ ♣♥ s♦ t ♦ss ♥t♦♥♥ s −♠(ǫ−1) ♥ ts ♣♣r♦①♠t♦♥ s q t♦ ǫ2/(ǫ21 + ǫ22)r r♦♥s ♥ st♥s

rst② ♦sr tt t ♥ ①tt♦♥ r♦♥ ①t♥s ♣ t♦ ❱ r ♣rt ♦ ǫ s ♠♥② s ♦ ss ♦st♦r ❬❪t ♥ss r♦♠ ♣♦st t♦ ♥t r♦♥ ♥ ❱ ♥♦rrs♣♦♥♥② ǫ2 s♦s ♠①♠ ♦ s♦r♣t♦♥ t ts rq♥s r ♣rt ǫ1 ♥ss r♦♠ ♥t t♦ ♣♦st t ♥ t ❱ ♥♦ts♥ ♥ t r s ♦ t s♠ r♦♥♥ ♦ss ♥t♦♥ ♦♥sq♥t② s♦s t♦ ♣s t ts s ♦ t ♥r② ♥ t s♦r♣t♦♥s♣tr♠ ǫ2 t str♦♥ s♦r♣t♦♥ ♦ ❱ st♠s r♦♠ tr♥st♦♥s r♦♠t ♥ ♥ t♦ t g stts s♦r♣t♦♥ ♥ ①t♥♥ ②♦♥ ♣ t♦ ❱ s ss♦t t tr♥st♦♥s r♦♠ t ♥ ♥ t♦ 2g

stts ♥ t ♦♥t♦♥ ♥ s♠ s♦r♣t♦♥ ♣ t ❱ ♦♠sr♦♠ ♥ ♥ t♦ 1g ①tt♦♥s ♦r ts r ♥ ♥ ❬❪

♦♥② s tt ♦ ❱ ♦rrs♣♦♥♥ t♦ t ③r♦♥♠ 4p

①tt♦♥s ǫ1 s♦ s s tr♣ ss ♦st♦r t ♥ss r♦♠

Page 44: Some ab initio tudies of the physical properties of materials

P ❯ ❨ P

♣♦st t♦ ♥t t ♥ ❱ ♦♥sq♥t② ǫ2 s♦s str♦♥s♦r♣t♦♥ t ❱ ♥ t♥ ♥ ❱ Ps r ♦sr ♥t ♦ss ♥t♦♥ ♥ ǫ1 ♥ss r♦♠ ♥t t♦ ♣♦st t ♥ ❱

r② ♦ t♦ ♣♦♥t ♦t tt t r♦♥ t♥ t ♥♣s♠♦♥s ♥ t 4p ♣s♠♦♥s r♦♥ t♦ ❱ ♥♥♦t ♥tr♣rt ♥ tr♠s ♦ ss ♦st♦rs t♥ ♥ ❱ ǫ1 ♥ ǫ2 r♦♠♥t ② ♥r trs ♥rs♥ ♦r ǫ1 ♥ rs♥ ♦r ǫ2 ♦rrs♣♦♥♥ ♦ss ♥t♦♥ ①ts r♦♥ ♣ t ❱ ss♥ ♥♦t t♦ ♣s♠♦♥s t t♦ ♦tr ♦r♠s ♦ ♦t ①tt♦♥s ♣s♠♦♥ s ♥ ② ♥s♥ r ♣rt ♦ t tr ♥t♦♥ ♥ ♠♥♠♠ ♦ t ♠♥r② ♣rt s ♥♦t t s ♦r ts ♣ ♥r ♦r ♦r ǫ1 ♥ ǫ2 s r② ♥ ♦sr ♥ t t♦rt ♦ rt 2 ❬❪ ♦r ♥♦t tt r t ♦st♦rs ss♦t t t 2s tr♦♥s r ♣rs♥t ǫ1 ♥ss r♦♠ ♣♦st t♦♥t r♦♥ ❱ ♥ ♥ss r♦♠ ♥t t♦ ♣♦st r♦♥ ❱ t r ♦r♠ ② t ♥r ♦r ♦ ǫ1 ♥ ǫ2 s ts ♦ t ♠♥ ♣ t ❱

♦ ts

♦r②

♦ ♥ ♦ s ♦♥ rst s t♦ t χ0 s ♥ t ♣r♦s st♦♥ ♥ t♥ t♦ t t rs♣♦♥s ♥t♦♥ χ q ♥rs tr ♥t♦♥ s t♥ ♦♠♣t r♦♠ q ♥ t ♠r♦s♦♣ ♠t s t♥ q

② ♥tr♦ ♦ ts s t♦ t ♥t♦ ♦♥t t ♦♦♥ ♠♥ts G = G′ ♦ t r♦s ♠trs χ0 χ ♥ ǫ−1 ♥ ♠tr①♥rs♦♥s ♦ qs ♥ s t♦♥ ♦♠♣♦♥♥ts ♦rrs♣♦♥t♦ ♦♣♥ t♥ ♦♥t♥ ♥ tr♥srs str♥s ❬❪

♠①♥ ♦ t ♦r♠r② ♥♣♥♥t tr♥st♦♥s ♦ tr♥t② sr ② t ♦♥♣t ♦ ♥ tr♦♥♦ ①♥ ❬❪

sts

♦ ts rt t ♥♦♠♦♥t② ♦ t ♠tr ♥ t rs♣♦♥s ♥t♦♥ ♥ t t ♦ ♠①♥ t ♦r♠r② ♥♣♥♥ttr♥st♦♥s ♥ ❩r2 p stts r t♦♠ t t② t ♥trt♦♥ t ♥♦r♥ t♦♠s ♥ ♦ ②r③ st②❬❪ ♦ ts r ♦♥ t♦ str♦♥ t ts s ♦ t ♥r② ② ♥tr♦

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r ❩r2 t♦rt tr ♥t♦♥ t q0 ♦♣ ♣♥ r ♣rt ♥tr ♠♥r② ♣rt ♦tt♦♠ ♣♥ t ♦ss ♥t♦♥ ♦♥s P t ♦ s s ♥ P t♦t ♦ s r ♥ ♠♥r② ♣rts ♦ t tr ♥t♦♥ rs♣ t ♦ss ♥t♦♥r r♦♥ t ♦r♥t③♥ ♦ ❲ t t ♠①♠♠♦ ❱ rs♣ ❱ r♦♠ ❬❪ r♦♠ ❬❪

Page 46: Some ab initio tudies of the physical properties of materials

P ❯ ❨ P

r 2 ♦ss ♥t♦♥ ♥ t r♦♥ ♦ t p tr♦♥ ①tt♦♥s t ♣♥ t♦t ♦ s t ♣♥s t ♦ s❯♥♣s

t srr♦♥♥s ♥ ♥ ♦trs ♦ ♥r♦♥♠♥t

s s♦♥ ♥ t s♦ ♥s ♦ ❩r2 ♥ ♥ t ts♦♥ ǫ1 ♥ ǫ2 r ♦ ❱ t r ♥r② ♦r t② rst② ♠♦② t tr♣ p ♣s♠♦♥s ♦t ♥ ♥s♣ ♥ ♣ ♣♦st♦♥♥ ❩r2 t ♣ ♦r♠r② t ❱ s st t♦rs r ♥r② ② ❱ t ♠♥ ♣ s st ② s ♠ s ❱

♦ t ♥ ♥s♦tr♦♣②

r ts ♦♥ ①tt♦♥s r♦♠ qst♦♠ t♦ ♦ s s♠r② ♥ ♦♥ ♦r t p ①tt♦♥s ♥ rt 2 ❬❪ t♦rt s ttr♦♥ r②st r t s②♠♠tr② s rs t rs♣tt♦ t ♦♥ t s♣tr ♦r ♠♦♠♥t♠ tr♥sr ♣r ♦r ♣r♣♥r t♦ t ttr♦♥ ①s r r② ♦s t ♣♥ ♦ ts ♥rs t r♥ ♥ t s♣tr♠ t♥ ♦r ♠♦♠♥t♠ tr♥sr ♣r ♦r ♣r♣♥r t♦ t ttr♦♥ ①s rt ♣♥ s ♦ ts ♥rs t ♥s♦tr♦♣② ♥ t s♣tr ♥ ♦tr ♦rs t ♥s♦tr♦♣② ♦sr ♥ t ❱ r♥ ♥rt 2 ♠♥② ♦♠s r♦♠ ♦ ts

♦♠♣rs♦♥ t ①♣r♠♥ts

♦♠♣rs♦♥ t ①♣r♠♥ts s ♥♦t strt♦rr ♥ ①♣r♠♥ts t♦sr ♥t♥st② ♣♥s ♦♥ ♥ ♥trt♦♥ ♦ t s♥ ♦r t ♦t♦♥

Page 47: Some ab initio tudies of the physical properties of materials

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r 2 ♦ss ♥t♦♥ t ♥t ♠♦♠♥t♠ tr♥sr s P t ♦ ts ♦ ♥ ①♣r♠♥t ♥srt s Pt♦t ♦ ts r♦♠ ❬❪

♥ β ❬❪ ♦r ♣s s ①♣rss ② t ♦r♠

I (E ) ∝ −π♠[

ε−1 ln

(

1 +β2

θ2E

)]

,

r θE = E♦ssm/~2k2

0 s t rtrst ♥ ♣♥♥ ♦♥ t ♥r②♦ss E♦ss ♥ ♦♥ t rtst ♠ss m ♥ t♦r k0 ♦ t ♥♥ttr♦♥ ♠ s s t♦ t♥ ♥t♦ ♦♥t t♦ ♣r♦ t♦rt♥trt ♦ss ♥t♦♥ ♣♥s ♦♥ t s②♠♠tr② ♦ t r②st♥ ♦♥ t ①♣r♠♥t ♦♥t♦♥s ❬ ❪

❲♥ ts s ♦♥ rt ♣ ♣♦st♦♥s t♥ t ♦t ①tt♦♥ t ♠ ♥r② t♥ t ♥ ♥ p ♣s♠♦♥s s r♣r♦♦t ♥ rt ❬❪ ♥ ♥ ③r♦♥ ❬❪ t♦rt s♣tr ♥t♥st②♦ t ♥ ♣s♠♦♥ t ❱ s ♦r t♦♦ s♠t ♣rt② ttrt t♦ t t② ♥ t ①♣r♠♥t ♥ ①trt♥t ♥st ♣rt r♦♠ t r st ♣ ③r♦ ♦ss ♦♥trt♦♥ t♥s♥② s♠ ♠♦♠♥t♠ tr♥sr ts ♠t s♦ ♣rt② ♦♠ r♦♠①t♦♥ ts ②♦♥ t P ❬❪

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r ♦rt ♦ss ♥t♦♥ t♥ t P t♦t ♦ s♥ t ♦ ts ♦tt ♥ c❩r2 s ♥ t❩r2♦ ♥ m❩r2 ♦ss ♥t♦♥ s r♦♥ t ♦r♥t③♥ ♦❲ ♦ ❱ r♦♠ ❬❪

♦♠♣rs♦♥ ♠♦♥ r♥t r②st

♣ss

ts ♦ ♥s♦tr♦♣② s♥ ♥ ♣r♦s st♦♥ ♥ rtr st② ♦♠♣r♥ s♣tr ♦ r②sts t t s♠ ♦♠♣♦st♦♥ t t r♥t r②st s②♠♠tr② ♦ ts ♥ ♦♠♣rs♦♥ ♦ s♣tr t♥ r♥t ♣ss ♦ ③r♦♥ s ♥ ♥rt♥ ❬❪

♦♥ tt ♥ t t♦♥s t ♥ ♣s♠♦♥s s s t 4p ♣s♠♦♥s r ♦t ♥ ♣ ♣♦st♦♥ ♥ s♣ ♥ t tr ♦♣rssr ♣ss ♦ ③r♦♥ r s r♥s t♦ ♦r♥s ♦r t ♥ ♣s♠♦♥ t r♥ ♥ t ♥s♣ rt② rss r♦♠r♥s ♥ t ♥ strtr t♥ t ♣ss t ♣ ♥ t ♦♥t♦♥ stts ❬❪ ♦r t 4p ♣ N2,3 t r♥ s r♦t♥ t ♦ ts

s r♥s r ♥♦t ♦sr ♥ t ①♣r♠♥t r ♣rt②s t r② ♦ t ♠sr♠♥ts s ♥♦t ②t ♥♦ ♦r tsr♥s t♦ s♥ ♣rt② s ♦ t t② t♦ s②♥ts③ ♣♣r♦♣rt s♠♣s ♣rtr ♣s r♠ ♦ ③r♦♥ t ♠♥② ♣str♥st♦♥ ♥s ♠s t t t♦ r♦ ♠♦♥♦♥ ♦r ttr♦♥ s♥r②sts ♥ ts rs♣t ♦r s♣tr♦s♦♣② s s tr♦♥ ♥r②♦ss♥r s♣tr♦s♦♣② ❬ ❪ s♠s t♦ rtr ♣♦t♥t ♦r trtr③t♦♥ ♦ r♥t ♣ss

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r ♥trt ♦ss ♥t♦♥ s t①t ♦r ♣r ③r♦♥ ♠♦♥♦♥ ttr♦♥ ♥ ♣ss ♦ ♥ ①♣r♠♥t s♥ t♦r② t ♦ s ♥srt t♦r② t♦t ♦ s t♦rt rs ♥ ♦♥♦t t ❱♦t ♣r♦ ss♥ ♦ ❲♦ ❱ ♥ ♦r♥t③♥ ♥t♦♥ ♦ ❲ ♦ ❱ ♥ t ①♣r♠♥t ③r♦♥ s ②ttr st③ r♦♠ ❬❪

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♥♦♠ Ps ♣♣r♦①♠t♦♥ s

♦♦ ♣♣r♦①♠t♦♥ ♦r

♥ t ♣r♥ st♦♥s r♣♦rt s♣tr t t♥t P t ♥s♥ ♠♦♠♥t♠ tr♥sr q ♦r ❩r2 ♥ stst♦r② r♠♥t t ①♣r♠♥t t ♥ ts s tr ♥ ♠♥② s②st♠s Ps ♦r ♥♦t s♥t ♦r s♦r♣t♦♥ s♣tr ❬❪

♥ t t♦♥ ♦ ♦t q = 0 ♥ s♦r♣t♦♥ s♣tr t ♥r♥ts r s♠r t ♦♠♣♦♥♥ts ♦ t ♥♣♥♥t♣rt rs♣♦♥s♥t♦♥ ♥ t r ♦♦♠ ♣♦t♥t ♥ tr♦r t sr♣♥② st rst st ♥tr♥ sr♣♥② s r♥t② ♥ ♥rst♦♦ ♥t ♦♦♥ ② ❬❪

♥ s♦♥ t♦ ♠t♠t② ♣r♦♣♦rt♦♥ t♦

−ℑ[ limq→0

v0(q)χ00(q,ω)],

r v0 s t G = 0 ♦♠♣♦♥♥t ♦ r ♦♦♠ ♣♦t♥t ♥ χ00 s t♠r♦s♦♣ rs♣♦♥s ♥t♦♥ s stt ♥ qs ♥ ❲t♥ tP q ♦♠s

χ = χ0 + χ0vχ,

♥ t ♦♠♣♦♥♥ts ♦ t r ♦♦♠ ♣♦t♥t v ♥tr ♥ q t s♦rtr♥ s s t G = 0 ♦♥r♥ ♦♥s

♥ t ♦tr ♥ t ♠♥r② ♣rt ♦ t ♠r♦s♦♣ tr♥t♦♥ ♥ s♦♥ t♦ ♣r♦♣♦rt♦♥ t♦ ♠♦ qt♦♥

−ℑ[ limq→0

v0(q)X00(q,ω)],

r t ♠♦ rs♣♦♥s ♥t♦♥ X rs ♠♦ ②s♦♥ qt♦♥

X = χ0 + χ0v X ,

r ♥♦ ♦♥② t s♦rt r♥ ♦♠♣♦♥♥ts ♦ t r ♦♦♠ ♣♦t♥t♥tr

v(G = 0) = 0,

v(G) = v(G).

①t♦♥ ts r ♦♥r♥ t r♦r t ♥tr♦t♦♥♥ t t♦♥ ♦ t ①t♦♥ ts ♦♥② st② ② ♠♦s tt♦rt s♣tr rs t ♦♥sr② ♠♦s t s♦r♣t♦♥s♣tr♠❬❪ s s s ♥ tr♦♥ ♥r② ♦ss s♣tr♠ r② ♦♥t♥s ♦♥r♥ ♣rt rs ♥ s♦r♣t♦♥ s♣tr♠ ♦s ♥♦t ♦♥t♥

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♥② ♦♥r♥ ♣rt t♥ t P ♣♣r♦①♠t♦♥ ♥ t ♥r t ♣s♠♦♥ ♥r② tr s ♥t♦♥ t♥ t ♦♥ r♥ tr♠ ♥ tqs♣rt st t st ♥ t ♦♥ tr♦♥ ♥r② ♣r♦ ② ts♥r② t♥ ♥t♦ ♦♥t t t tt tr♦♥s ♠♦ ♥ ♠♠s sst♦♥

♦♥s♦♥

♣rs♥t t t♦rt r♠♦r t♦ t tr♦♥ ♥r②♦ss s♣tr r♥♦♠ ♣s ♣♣r♦①♠t♦♥ s s♦♥ t♦ qt♦r ♦t tr♦ ①♠♣s ♦♥ ❩r2 ♥ 2 ♥ ♦♥ ♠t♠tr♦♥s s♦ rss sr tr rt② ♦r ♥ ♦♦rt♦♥t ts ♦ t ♥s♦♥ ♦ s♠♦r stts ♥ t ♥ ♥ 2 ♥2 ❬❪

Page 52: Some ab initio tudies of the physical properties of materials

♣tr

♦rt rsts ♦♣ts♦r♣t♦♥ ①♣r♠♥t

♥ t ♦♦s ♦♠♣r t s♦r♣t♦♥ s♣tr♠ ♦ ♣♦②r②st ♦③r♦♥ s ♣♣♥① t t t♦rt sr♣t♦♥ t♥ t r♦ss ❬❪ ♥ t s♦r♣t♦♥ s♣tr♠ ♦ s♥ r②st ♦ 2 tt♦rt sr♣t♦♥s t♥ ②♦♥ ♦♥♣rt t♦r② ❬❪

❲ ♦♥sr ♥ ♦♣t s♦r♣t♦♥ ①♣r♠♥t ♥ ts s ♦♥ ♠srs t s♦r♣t♦♥ ♦♥t

α(ω) =ωℑ(εM(ω))

n1(ω)c,

r c s t t ♦t② ω s t ♥r② ♦ t s♦r ♣♦t♦♥ n1 st r ♣rt ♦ t ♥① ♦ rrt♦♥ ♥ ℑ(εM(ω)) s t ♠♥r② ♣rt♦ t ♠r♦s♦♣ tr ♥t♦♥

❲ ♥ t♦ t t ♠r♦s♦♣ tr ♥t♦♥ rs

εM(ω) = limq→0

1

ε−1G=0G ′=0(q,ω)

.

t♦rt s♦r♣t♦♥ s♣tr♠ s t♥ ♥ ② t ♠♥r② ♣rt ♦qt♦♥

❲t♥ ♥♣♥♥t tr♥st♦♥ t♦r②

s♦r♣t♦♥ ♦ ♣♦t♦♥ ♦s ♦♥ tr♦♥ ♦ t ♥ ♥ t♦ ♣r♦♠♦t t♦ ♦♥t♦♥ stt ♥ ♥ ♥♣♥♥t ♣rt ♣♣r♦①♠t♦♥ rt ♥ ①♣rss♦♥ ♦r t ♠r♦s♦♣ tr ♥t♦♥

εM ≈ 1 − vχ0(G = G′ = 0;q → 0),

♥ s t♦ t t t♦rt s♦r♣t♦♥ s♣tr♠

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♠♥r② ♣rt ♦ t ♠r♦s♦♣ tr ♥t♦♥ εM rs

ℑ(εM(ω)) =4π

ω2

v ,c

|〈ψc | − iA.∇|ψv〉|2δ(ω − εc + εv)

r −iA ·∇ srs t ♦♣♥ ♦ t tr♦♥ t t t♦r ♣♦t♥t A ♦ t tr♦♠♥t ❲ trt ts tr♠ t♥ t ♣♦r♣♣r♦①♠t♦♥ s♠ s ♣r♦r♠ ♦t ♦♥ t ♥t ♥ ♥ ♥♦♥t♦♥ stts ♥ q r ♦ stts ♦ t ♣r♦ ♣♦t♥t ♥ t s♦

s r♠s ♦♥ r s ♣♣♥① ♦♠s r♦♠ t t tt ♦♥trts t tr♥st♦♥s t♥ stts ♥♣♥♥t② ❯s♥ qt♦♥ ♦rqt♦♥ ♦r t ♣♦r③t② ♥ t♥ t ♠t G = G′ = 0;q → 0t rs♣♦♥s ♥t♦♥ χ0 ♦ st♦♥ ♠♦♥ts t♦ t r♠s ♦♥ r♦ q

♦♥t ♥st② ♦ stts

s♠♣st ♣♣r♦ t♦ t s♦r♣t♦♥ s♣tr♠ ♦♥ssts ♦ t t♦♥ ♦ t ♦♥t ♥st② ♦ stts s rst tt♠♣t t♦ ♦t♥ t♦rttr♦♥ s♣tr ♥ s t ♥s εi ♦ t ♠t♦♥♥t♦ t t ♦♥t ♥st② ♦ stts

v ,c δ(ω − εc − εv) rεv s t ♥r② ♦ stt ♥ t ♥ ♥ ♥ εc s t ♥r② ♦ stt ♥ t ♦♥t♦♥ ♥ s ♣♣r♦①♠t♦♥ s♣♣♦ss tt t ♠tr①♠♥ts |〈ψc |− iA ·∇|ψv〉|

2 r ♣t ♦♥st♥t ♥ qt♦♥ q♥tt②

ℑ(ǫ(ω)) =

v ,c δ(ω − εc + εv)

ω2,

r♣♦rt ♥ ❩r2 s rt t♦ t ♦♥t ♥st② ♦ stts s♥ ♦s ♥♦t sts② ♦♥srt♦♥ rs ♥ tr♦r t t s♣tr♠ s ♥ rtrr② ♥ts

s♦s ♦♦ ♦r r♠♥t t♦ t s ♥♦t s♥tt♦ ♥tr♣rt t ts ♦ t ①♣r♠♥t t r s②♠♦s s♣②t♥ ♥ ❱ ♥ r♦♥ ❱ ♥ ♣rtr t ♦r s♣♦ t s♣tr♠ s ♥♦t r♣r♦

t ♦ ♠tr① ♠♥ts

s♠♣st ♦ ♣♣r♦①♠t♦♥ ♦♥ ♥ ♠ ②♦♥ t s t♦trt t ♣rts ♥ t tr♥st♦♥s t♥ stts ♥♣♥♥t② tqt♦♥

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r s♦r♣t♦♥ s♣tr♠ ♦r ♠♦♥♦♥ ❩r2 t s♥ tP t ♦ s s♦ ♥ P t♦t ♦ s ♦tt ♥♥ t t rt♦ ♦ t ② t sqr rq♥② ♦♠♣r t①♣r♠♥t rsts r♦♠ r♥ t rr♥ ❬❪ t♦rtrs ♥ s t♦ t ♥t♥st② ♦ t ①♣r♠♥t ♣ r♦♥ ❱ r♦♠ ❬❪

s ♣♣r♦①♠t♦♥ s s♦♠t♠s s♥t ♦r s②st♠s t ♥♦♠♦♥ts ♦r t ♠t sr♥♥ ♠♦♥ r♥t ①♠♣s ♦♥ ♥t t s♦r♣t♦♥ s♣tr♠ ♦ s♠ ♠tr ♥♥♦ts ♥ t t s♣♦r③ ♦♥ t ♥♥♦t ①s ❬ ❪

♦♠♣tt♦♥ ♦ t ♠tr① ♠♥ts |〈ψf | − iA · ∇|ψi〉|2 ♥ q

s ♥ssr② t♦ ♠♣♦s t st♦♥ rs ♥ ♦♣t s♦r♣t♦♥ ts s ♦♠♣♦rt♥ ♥ ♦♥ s ♠♦♥♦r②st ♥ ♥ts t♦ st② t ts ♦t ♣♦r③t♦♥ ♦ t

♥ ♥ r t s♦r♣t♦♥ s♣tr♠ ♦r t ♣♦r③t♦♥sr ♠tr① ♠♥ts ♦ ♣r♠r② ♠♣♦rt♥ ♥ r s tt t♦r s♣ ♦ t s♦r♣t♦♥ s♣tr♠ s ♥ rt② ♠♦ ② t♥s♦♥ ♦ ♠tr① ♠♥ts

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②♦♥ ♥♣♥♥t tr♥st♦♥ t♦r②

♠r♦s♦♣ tr ♥t♦♥ ε(r, r′,ω) ♥ rtt♥ ♦rr tr♥s♦r♠ s t ♠tr① t ♠♥ts εGG′(q,ω) ♦ qt♦♥ ❬❪

♠♠r③♥ qt♦♥ rt t ♥rs tr ♥t♦♥ s

ε−1GG(q,ω) = 1 + v(q + G)χGG(q,ω),

r v s t ♦♦♠ ♣♦t♥t ♥ χ t ♣♦r③t② ♦ t s②st♠st♦♥

♥ ♦rr t♦ t ts ♥t♦♥s ♥ t♦ ♦r♠t ♥ ①♣rss♦♥ ♦r t ♣♦r③t② ♦ t s②st♠ χ t ♥ t ② ②s♦♥s qt♦♥ ♦r s ♣♣r♥t② r r♦♠ r♠s ♦♥ r♣♣♥① ♦♥tss ♦♥ ♥ s♦ tt ♥ r ①♣rsss ♥ tr♦♥♦ ①♥ ❬❪ t ♠♥r② ♣rt ♦ t tr♥t♦♥s s ♥ ② qt♦♥

♦ ts

♥♦♠♦♥ts ♦ t s②st♠ rs t♦ t r②st ♦ ts♥ ♦r t♦♥s ts ♦ ts rs r♦♠ t ② t ♦♦♠tr♠ v s trt ♥ st♦♥

❲ ♥ ♥t t ♦ ts ♥tr② ② ♥♥ ♦♥② t ♦♥r♥ ♣rt ♦ t ♦♦♠ ♣♦t♥t vG=0(q) s ♦♥ ♥ st♦♥ r② ♥♦rs t ♠r♦s♦♣ ♦♠♣♦♥♥ts ♦ t ♥ ♥ts s ♦♥② ♥ t♦ t t ♦ t tr ♠tr① εG=0,G′=0 ♥ s t P t♦t ♦ s ♦ st♦♥

♥ ♥ t ♦♦♠ ♣♦t♥t vG(q) ♥ t♦ tt tr ♠tr① ♥♥ t ♦♦♥ ♠♥ts εG,G′ 6=Gtst ♥rs♦♥ ♦ ts ♠tr① s t t ♦ ♠①♥ t ♣r♦s② ♥♣♥♥t tr♥st♦♥s

♦r st ♥♥ t ♦ ts ♦s ♥♦t r♥t ttt rsts s♥♥t② ♦sr t♦ ①♣r♠♥t t♥ t♦♥s rt② r ♥t s s s♣② tr ♥ t s ♦ s♦r♣t♦♥ s♣tr♦r ♦r tr♥st♦♥♠t ♦① s②st♠s ♦r ①♠♣ ♥ r ♣♦tt ①♣r♠♥t rsts ♦r ♠♦♥♦♥ ❩r2 ♥st t♦rt Pt♦♥s ♦t t rtr ♦ ts ♥ t♦t t♠ ❲♥ s tt tr s r r♥ t♥ t rsts ♦ t t♦ t♦rt ♣♣r♦①♠t♦♥s ♥ ♥ ♣rtr t② s♦ r ♥ t ♥r②r♦♥ ♦r s ♦ t ♥r② rr t♥ ❱

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♥ ♥ ♦♣t s♦r♣t♦♥ ①♣r♠♥t q s ♦s t♦ ③r♦ ①♥ ♥♦rrt♦♥ ♦ ts ♥ s♦♥ t♦ s♠ ♥♥ ♥2 ♦r ♥s♥ q ❬❪ ♥ tr♦r t② ♥♦t ♥ t♥ ♥t♦ ♦♥t ♥ t t♦♥s ♦ r

s♣rts ts

♦r s♦r♣t♦♥ s♣tr t qs♣rt ♥r② sts tt ♦♥ ♥ t ♥ t GW ♣♣r♦①♠t♦♥ ❬ ❪ s ♥ssr② t s② t s ♥♦ts♥t ❬❪

❲ ♣♣r♦①♠t♦♥ ♦♥ssts ♦ s♦♥ ♥ qt♦♥ s♠r t♦ ts②st♠ ♦ qt♦♥s ♥ ♥ t ♦ ①♥ ♥ ♦rrt♦♥ ♣♦t♥t vxc(r) s r♣ ② ♥♦♥♦ ♥ ②♥♠ s♥r② ♦♣rt♦rΣ(ω, r, r′)

HKSψn(r) − vxc(r)ψn(r) +

d3r′Σ(ω, r, r′)ψn(r′) = εQP

n ψn(r).

♥ t s♠♣st ♦r♠t♦♥ t s♥r② Σ(ω, r, r′) s t tω = εQP

n t s ♣♣r♦①♠t ② t ♣r♦t ♦ t r♥s ♥t♦♥ ♥♦ t sr♥ ♦♦♠ ♥trt♦♥ W = ǫ−1v ♥ t ♥♠ GW ♦rts ♣♣r♦①♠t♦♥ ♥ rst st♣ ♥s r ♦rrt ② qt♦♥ t ♥t♦♥s r ♥♥ ♥ r s② t♦s ♦t♥r♦♠

♥♥ qs♣rt ts ♥ t tr♦♥ s♣tr ♦rrts t ♥♣s ♥ t♦♥s t②♣② ♥ ♣s r♠ t♦♦ s♠ t rs♣t t♦ t ♣♦t♦♠ss♦♥ ♣ s rsts ♥ ♠♣r♦ ♣♦♥ s♥ ♠t♦s s s t ❲ ♣♣r♦①♠t♦♥ ❬❪ ❲ st♠t♦♥ ♦ t ♥ ♣ ♥ ♠♦♥♦♥ ❩r2 s rst ♦ ❱❬❪ ♥st ♦ t ♦ ❱ ❬❪

❲♥ d tr♦♥s ♦♠ ♥t♦ ♣② ♦r t s♠♣st ❲ ♣♣r♦①♠t♦♥ s ♥♦ ♦♥r s♥t s s ♥ s♦♥ ♦r 2 ❬ ❪ GW st♠t♦♥ ♦ t ♥ ♣ ②s ❱ t♦ ♦♠♣r t ❱ ♥ t ①♣r♠♥t r♦r ♦♥ ♥s t♦ ♦ ♦♥ st♣ rtr ♥ tt♦rt r♠♦r ♥ s t s ♦ t qs♣rt ♥r② ♥ t①♣rss♦♥ ♦ t ♥rs tr ♥t♦♥ ǫ−1 t♦ rt t sr♥♦♦♠ ♥trt♦♥ W s♦♥sst♥t GW ♣♣r♦①♠t♦♥ ❬❪ s♦♣ ♥ rt ② r♥ r♥ s P tss t t♣ ♦ t s♦ ❳ ♣♣r♦①♠t♦♥ ❬❪ ♣ ♦ 2 st t♦ ❱ ♥ t s ❳ ♣♣r♦①♠t♦♥ ♥ ❱ ♥t s♦♥sst♥t GW

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r s♦r♣t♦♥ s♣tr♠ ♦r 2 t♦t ①t♦♥ ts t s♥ t P t ♦ s t t ♦tt ♥ tt GW s ♥ ♥ t t s♦♥sst♥t ❲ s♦ ♥♦♠♣r t ①♣r♠♥t ♦ ❬❪ rs r♦♠ ❬❪

♦ strt ts t s♦ ♥ r t♦rt s♣tr tt qt♦♥s ♥ t♦tr t ①♣r♠♥t t ♥ qt♦♥ t s ♦ t ♥r② ♥ ♥t♦♥s ♦ t ♥t ♥ ♥ stts ♥ t t r♥t s ♦ ♣♣r♦①♠t♦♥ t t s ♥ r t t GW ♥ t t ♦ s♦♥sst♥tGW ♣♣r♦①♠t♦♥ ❬❪ ♥② t t ttr s t t♦rt s♦r♣t♦♥ ♦sr t♦ t ①♣r♠♥t ♦♥ ♥ ♥ rs r♦♥ ❱

♦r s♦r♣t♦♥ s♣tr t qs♣rt ♥r② st tt ♦♥ ♥ t ♥ t GW ♣♣r♦①♠t♦♥ s s② ♥ssr② t ♥♦t s♥t ss s♥ ♥ t ♦r s♣ ♦ t t♦rt s♣tr r ♥ t ♠♦r ♠♦t♦♥ s r♦t ♥ t s♦r♣t♦♥ s♣tr♠ ② ①t♦♥ts s s s t r♥ t ♥ s♣tr♠ s st♦♥ ♥ s♦r♣t♦♥ s♣tr♠ ♦s ♥♦t ♦♥t♥ ♥② ♦♥ r♥ ♣rt t♥t P ♣♣r♦①♠t♦♥ ①t♦♥ ts ts ♦♥sr② ♠♦② ♥ s♦r♣t♦♥ s♣tr♠ s strt ♥ t ♥①t st♦♥

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P ❯ PP ❳P

①t♦♥ ts

♥ ♥t♦ ♦♥t t ①t♦♥ ts s ♦♠♣① ♥ s ♥ ♥②♦rt ② rt ♥ ts P tss ❬❪ ♥ ♦♥② r♦♠♠♥ tr♥ ♦ ts P tss t ♠♦♥ts t♦ s♦♥ t♣tr qt♦♥♦r ♦r ♣♦♥t ♣♦rst② P

P = P0 + P0ΞP

Ξ s t ♥trt♥ r♥ ♥ ♦♥ssts ♦ t ①♥ t t ♦ ♦ ♦ st♦♥ ♥ ♦ t ♦♦♠ tr♦♥♦ ♥trt♦♥sr♥ t t ♣♦t♥t W ♦ t ♣r♦s st♦♥

♦ qt♦♥ ♠♦♥ts t♦ ♦♥③♥ ♥ t ♠t♦♥♥ rs♦♥♥t ♣rt ♦ t ♠t♦♥♥ ♦♥ssts ♦ t r tr♦♥♦ ♣r ♥r② ♣s t t♦ ♦♠♥t♦♥ ♥trt♦♥s ①♥ ♥sr♥ ♦♦♠ tr♦♥♦ ①♣rss ♥ t r♥ Ξ

Hexccv ;c ′v ′ = (εc − εv)δvv ′δcc ′ − iΞcv ;c ′v ′ .

s ♦ t ①t♦♥ ♥r② Eλ ♥ ♥t♦♥ ♦♥ts Acvλ

r t ♥s ♥ ♥t♦rs ♦ t t t♦♣rt ♠t♦♥♥ ♦r t tr♦♥♦ ♣rs Hexc

Hexce1,h1;e2;h2

Ae2,h2λ

= EλAe1,h1λ

,

♥ ei s ♥ tr♦♥ stt ♥ t ♦♥t♦♥ ♥ ♥ hi s ♦ stt ♥ t ♥ ♥

♠t♦♥♥ s ①♣rss ♥ t ss ♦ tr♦♥♦ ♥t♦♥s |ψvψc > tr♦♥♦ ♣r ♥t♦♥ s s② ①♣rss s|ψvψc > r |ψv > ♥ |ψc > r s♥ ♣rt s♦t♦♥s ♦ t qt♦♥s ①t♦♥ ♠♣t s ①♣rss s ❬❪

Ψλ(r, r′) =

(c,v)

Ac,vλψ∗

c (r)ψv(r′).

♥ t tr ♥t♦♥ t ①t♦♥ t ♥ ② t sr♥♦♦♠ tr♦♥♦ ♥trt♦♥ s t♦ ♠①♥ ♦ t ♦r♠② ♥♣♥♥t tr♥st♦♥s t t s♠ ♥r② ❬❪

ℑ(εM(ω)) = 2π limq→0

vG=0(q)∑

λ

|∑

v ,c

|〈ψc | − iA.∇|ψv〉Acvλ|2δ(ω − Eλ + iα).

Page 59: Some ab initio tudies of the physical properties of materials

P ❯ P

P ❳P

♥t♦♥ ♦♥ts Acvλ

♠① t ♦r♠② ♥♣♥♥t tr♥st♦♥s♥ ♥ ♦r♥t ts ♥ r♠s ♦♥ r

♠t♥ Ξ t♦ t ①♥ t ♦ ts s strt② q♥t t♦ st♦♥ ♥ ♥t♦ ♦♥t ♦t t ①♥ t ♥ tsr♥ ♦♦♠ tr♦♥♦ ♥trt♦♥ ♥ Ξ ♥s rst ♥s ♥t ♦♣t s♣tr r ts ♦ t tr♦♥♦ ♥trt♦♥ ♥ s♥ ② ♦♠♣r♥ t s ♥ ♦ r ♥ t ♦ts ♥♦ ♣♥ ♦ r

t♦ t ♦ s♠ s ♥ s♦♥ t♦ s♥t ♦r sp♦♥ s♠♦♥t♦rs t s ♥♦t s♥t t♦ ♥tr♣rt t ①♣r♠♥ts♣tr♠ ♦ 2 ♣♥ ♦ r ♥srt♥ t ♠♣r♦ s♦ t qs♣rt ♥r② ♦t♦♥ r♦♠ s♦♥sst♥t GW t♦♥♥ t r tr♦♥♦ ♠t♦♥♥ (εc − εv)δvv ′δcc ′ s s♦ ♥♦t s♥ts♦tt ♥ ♦ ♣♥ ♦ r r♥ s s♦♥ tt ♦♥♥s t♦ ♦ ♦♥ st♣ rtr ♦r ♠trs t d tr♦♥s s t s ♦ t ♥r② r ♥♦t s♥t t♦ ♣r♦♣r② t t sr♥♥♥t♦♥ ǫ−1 ♥ t♦ ♦t♥ t sr♥ ♦♦♠ tr♦♥♦ ♥trt♦♥ W ❲♥ ǫ−1 s ♣r♦♣r② t s♦ ♥ t ①♣rss♦♥ ♦ Ξ s♦♥ ♥ ♣♥ ♦ r t♥ t t♦r② s ♣ ♥ ♥rst♥♥t ①♣r♠♥t s♣tr♠ ♦r rs ♥ ♣rs♥t t s

♦st♦♥ ♦ ①t♦♥ ts

s♦t♦♥ ♦ t qs♣rt ♥ ♦ t t♣tr qt♦♥ rr② ♠rs♦♠ t♦♥s

❲ ♠ ♥ tt♠♣t t♦ ♠♦ t ①t♦♥ t t♥ t r♠♦r ♦ t♠♣♥♥t ♥st② ♥t♦♥ t♦r② ② ♥♥ ♥ ♣♣r♦①♠t♦♥ ♦ t ♦♥ r♥ r♥ s α

|q|2 t α ♥ ♥ ♠♣r ♣r♠tr

r♦♠ t stt tr sr♥♥ ❬❪

♥ ♠② ♥rst♥♥ ts ♠♦♥ts t♦ ♥srt♥ ♦♥r♥ ♣rt α

|q|2♥

qt♦♥

F 0(q,Gω) = δVbare(q,G,ω)+∑

G′

[4πe2

|q + G′|2δ(G′ − G) + fxc(G

′ − G)]δn0(q + G′,ω),

Page 60: Some ab initio tudies of the physical properties of materials

P ❯ PP ❳P

r s♦r♣t♦♥ s♣tr♠ ♦r 2 t t ①t♦♥ tst t st♥r ❲ ♥s ♥ t ♥t♦♥s ♥ ǫ−1

♥ ♥ t r tr♦♥♦ ♠t♦♥♥ (εc − εv)δvv ′δcc ′ ♦t s ♥ qs♣rt ♦rrt♦♥s t♦ t ♥r② ♦t♥ r♦♠ s ♦♥sst♥t ❲ t♦♥ r ♥srt ♥ t r tr♦♥♦ ♠t♦♥♥(εc−εv)δvv ′δcc ′ s♦tt ♥ ♦r ♦t ♥ t r tr♦♥♦ ♠t♦♥♥ ♥ ǫ−1 s♦ ♥s ♥st ♣♥ s♦s t tr♥st♦♥ ♥②ss♦r ♣ ♦♥trt♥ tr♥st♦♥s ♦ts ♥ ♦♣t s♦r♣t♦♥ s♣tr♠t t t s♦♥sst♥t ❲ s ♦ t ♥r② t t♦t ①t♦♥ ts s ♥ ①♣r♠♥t ♦ ❬❪ rs r♦♠ ❬❪

Page 61: Some ab initio tudies of the physical properties of materials

P ❯ P

P ❳P

②♥

F 0(q,Gω) = δVbare(q,G,ω)+∑

G′

[4πe2

|q + G′|2δ(G′ − G) + fxc(G

′ − G) +4παe2

|q + G′|2δ(G′ − G)]δn0(q + G′,ω).

♥ ts stt ♦r♠ t s ♥♦t ♣♦ss t♦ rt ②r srs ♥ ♥ts②st♠ t ts ♠♦ t t s ♦♥♥♥ ♥ ♠♦②♥ t ♦♣t s♣tr ♦t♥ ♥ t♠♣♥♥t ♥st② ♥t♦♥ t♦r② ❬❪

①t♦♥ ts r t♦t t♦ r r♦♠ t ♥♦♥♦ ①♥♦♣rt♦r ❬❪ ts s s♦ P♦ss♦♥s qt♦♥ ♦ s♦ s♦ ♦♥②t t rtr ♣♦t♥t ❲ s♥ tt ♦r ♦♥ ♥t ♣rtrt♦♥ q = 0 ♥ G = 0 ♦♥ s δn(q+G,ω) = 0 ♥ ♥ ♥t ♥st② s ♥♦ ♠r♦s♦♣ ♦♠♣♦♥♥t t t♦t ♠r♦s♦♣ tr♦♥♥st② s ♣t ♦♥st♥t ♥ t ①t stt lim

q→0

[n(r)− < n >]e−iq.r → 0

♥ s s t r♥ ♠♦ α

|q|2s♦ ♥♦ t s ♥ q

t♦♥ t s ♠t♣ ② δn(q,G → 0,ω)

r♥t tt♠♣t ② ♠②s ♥ r♦ tt P ♥sttt ♥ér♦ t P②sq s ① ♦♥♥sés ❯♥rsté Prs ❱P r t♦ ♥tr♦ t ♠♦ r♥ ♥ t P qt♦♥s ♦ ❬❪ s ♥ ♠② ♥rst♥♥ ts r s ♦♥♥t t♦ tt tt ♥ ts s t ♥ ♥ ♥st② s s♥ t♦ ♥♦ ♠r♦s♦♣ ♦♠♣♦♥♥t s s ♥♦t t s ♥ t P ♣r♦r♠ ♣ s ♥ ❬❪ ♥ ♥♦ ♦ t ♥ ♥st② s ♣r♦r♠

♥ ♠② ♥rst♥♥ ♥tr♦♥ ♠♦ r♥ s ♦♥ ♥ ❬❪♠♦♥ts t♦ ♠♦②♥ P♦ss♦♥s qt♦♥ s ♠t stt♦♥ ♦♥sr tt t ♣rtrt♦♥ s ♥♦ ♦♥r t♥ s t ♠♥♦ ♦♥ t♦ ♦rt ♦♥ ts ♣♦♥t

♦♥ t ts

♥ s s ♦♥ s♦ t ♥t♦ ♦♥t t ♦♠♣♦♥♥t δn0 ♥ ②qt♦♥ ♥ P♦ss♦♥s qt♦♥

♥♥ rst t q♥tt② A ♣♣rs ♥ δn0 q ♥ ♥δnq(r) q ♦♥ s

Alk1pk2(r) =

Blk1pk2

ε(0)pk2

− ε(0)lk1

− ~ω − i~α,

Page 62: Some ab initio tudies of the physical properties of materials

P ❯ PP ❳P

t B qs t♦

Blk1pk2(r) = ψ

(0) ∗pk2

(r)ψ(0)lk1

(r)[f (0)(ε(0)pk2

) − f (0)(ε(0)lk1

)] < ψ(0)lk1|F q|ψ

(0)pk2

> .

rt♥ P♦ss♦♥ qt♦♥ t δn0 s t♦∑

G

|(q + G)|2 F 0Hartree(q,G,ω)e−i(q+G).re iωteαt + c .c . =

4πe2∑

lk1pk2

Alk1pk2(r)eαt(e iωt − e

−i(ε(0)lk1

−ε(0)pk2

) t~ ) + c .c .,

r t tr♠s e−i(ε

(0)lk1

−ε(0)pk2

) t~ ♦♠ r♦♠ ♥♦♥t tr♠s

♥trt♥ ♦♥ t♠ ♥ t♥ t ♦♥ ♥t ♠t ♥ tt

limq,G→0

|(q + G)|2 F 0Hartree(q,G,ω) = 4πe2 lim

q,G→0δn(q + G,ω)+

4πe2

~ωlim

q,G→0

lk1pk2

Blk1pk2(G)

❲ s tt ♥♦♥ t ♣rtrt♦♥ ♥s ♥ t♦♥ tr♠ t♦t r♥ ♦♠♥ r♦♠ t rtr ♣♦t♥t

4πe2

~ωlim

q,G→0

1

|(q + G)|2

lk1pk2

Blk1pk2(G).

s t♦♥ tr♠ s t ♦r α

|q|2 s ♥ rt ♥

①♣♥♥ ①t♦♥ ts ❬❪

❲tr s ♥♦♥ t ♦♥trt♦♥ ♦ t ♠♥ ①♣♥t♦♥ ♦r t ①t♦♥ t ♦ ❬❪ s t ♦r tr ♦r

♦♥s♦♥

♥ ts ♣tr ♣rs♥t r♥t s ♦ ♣♣r♦①♠t♦♥ t♦ t ♦♣t s♦r♣t♦♥ s♣tr ♣rs♥t stts ♦ t t♦r② s r②♠tr ♥ t r♦ ♦ ①t♦♥ t s ♥rst♦♦ st② ♣rs♥t ♥ ♥♣s ①♣♥t♦♥ ♦♥ t ♦♥ r♥ r♥ α

|q|2

♦ ♥tr♣rt s t ♦♥trt♦♥ ♦ ♥♦♥ t ♣rtrt♦♥

Page 63: Some ab initio tudies of the physical properties of materials
Page 64: Some ab initio tudies of the physical properties of materials

♣tr

♦rt rsts ♦♥ tstt② ♦ ♦r♦♥ rs

s ♣tr s r♣r♦t♦♥ ♦ t ♣r♣r♥t ❬❪ t s r rt ♦♠② ♦r ♦♥ ♦r♦♥ rs ♦♦♥ ♥ ♥tt♦♥ t♦ t t ♥tr♥t♦♥②♠♣♦s♠ ♦♥ ♦r♦♥ ♦rs ♥ t trs ♣t♠r ts ♠♥ ♣♥ ♠ ♥♦ ♦♥ t♦ ♣rs♥t ♥ rsts ♦♥t ♦r♠t♦♥ ♥r② ♦ ♦r♦♥ rs t r♦♥ ♦♥♥trt♦♥s ♦r t♥ t ♣♣r s ♥ rtt♥ ♥ ♦♦rt♦♥ t ♥ st♥ tr♥♥②

♥tr♦t♦♥

♥st② ♥t♦♥ t♦r② s ♦♠ r r♦♠rst♣r♥♣st♦♦ t♦ ♥stt r♦♥ stt ♣r♦♣rts ♦ ♠trs❬ ❪ ♦rt rsts ♦♥ ♦r♦♥ rs ♣rs♥t ♥ ts ♣♣r r② ♦♥ ♥tr♦r r② r ♥ ts ♥tr♦t♦♥ t ♠♥ ♣r♣♦s ♦ ♥ ts ♠tt♦♥s ♠♣s s②st♠ ♦ ♥trt♥ tr♦♥s ♦♥ s②st♠ ♦ ♥♦♥♥trt♥ tr♦♥s ♥ ♥ t ♣♦t♥t ♦♥t♥s ts♦ ①♥ ♥ ♦rrt♦♥ ♣♦t♥t ♥ t rs ♦♥ ss♠♣t♦♥s ♦r t ①♥ ♥ ♦rrt♦♥ ♥r② ♠ t ♠♦♥tr♠s t t♦ t ♥t♦ ♦♥t ♥ t ♠♣♣♥ t r♥ ♥♥t ♥r② t♥ s②st♠ ♦ ♥trt♥ tr♦♥s ♥ ♥♦♥♥trt♥♦♥s ♠♥②♦ tr♦♥tr♦♥ q♥t♠ ♥trt♦♥s s sPs ♣r♥♣ ②♦♥ t rtr ♥r② t ss tr♦stt ♥r② ♦r ♥trt♥ r ♥sts

♥ t s♠♣st ♦ ♥st② ♣♣r♦①♠t♦♥ s♠ ♦♠♦ t s②st♠ s ①♣t t♦ ♦♥trt t♦ t ♥r② ♦ ①♥ ♥ ♦rrt♦♥ s ♦ ♥ q ♦♠ ♦ ♦♠♦♥♦s tr♦♥ s t ts♠ ♥st②❬❪ qr♠ ♣r♦♣rts t t♥ ss tt ♣r♠trs ♥ ♥tr♥ t♦♠ ♣♦st♦♥s s② r ①tr♠②

Page 65: Some ab initio tudies of the physical properties of materials

P ❯

t♥ t ①♣r♠♥t r r ♦r ♥♠r ♦ ♣♣t♦♥s ♥ ts r② s ♥♦t ♥♦ t s ♦rt ♣♦♥t♥♦t ♦r ♥st♥ tt ♠♦st ♦ t♦②s t♦♥s ♦ tr♦♥ s♣tr r♣r♦r♠ t t ①♣r♠♥t tt ♦♥st♥t t♦ ♦ tt ♠st❬❪

①♥ ♥ ♦rrt♦♥ ♥t♦♥s ②♦♥ r ts rqr♥ ♦rr t♦ t t qr♠ ♦♠ t rtr r② ♥r③ r♥t ♣♣r♦①♠t♦♥s ♥ ♦♣ t s♥ ♦t❬❪ t s ♠♣♦rt♥t ♦r ♣r♦♣rts ①♣t② ♣♥ ♦♥t qr♠ ♦♠ Veq s s t t♥s♦r ♦ st ♦♥st♥ts Cijkl ♥ s t s♦♥ ♦rr rt ♦ t t♦t ♥r② E trs♣t t♦ t str♥ t♥s♦r εij r i , j , k ♥ l r rts♥ ♥①s

Cijkl =1

Veq

(

∂2E

∂εij∂εkl

)

ε=0

.

♥ t ♦ qt♦♥ t ①♣t ♣♥♥ ♦♥ t qr♠ ♦♠Veq ♠s t rr♦r r ♦♥ st ♦♥st♥ts ♠ s♠r ♥ tt♥ t ♥r③ r♥t ♣♣r♦①♠t♦♥ t♥ t♥ ❬❪ r ♠♥t rs♦♥♥ s ♥♦tr t②♣ ♦ ♣r♦♣rts rt②♣r♦s t ♦ t♦♠ strtr tr♦ t tr♦♥ rs♣♦♥s t♦ ♥ ①tr♥ ♠♥t ♦r t s♠ rs♦♥s t♦♥s ♦ t ♠st t♥s♦r ♣r♦r♠ t s ♦ s♦ ♠♦r stst♦r② r♠♥tt ①♣r♠♥t ♥ ♦♠♣rs♦♥ t t♦s ♦t♥ ② s♥ t ❬❪ ❲ tr♦r s ♦♥ ♦ t s ❬ ❪ ♦r ♦r rsts s♣tr♣rs♥t ♥ sst♦♥

♠♦♥ ♥♦♥ ♠tt♦♥s ♦ ♦r♥ ♥r② ♣s ♥ ♥st♦rs♥ s♠♦♥t♦rs r ♥rst♠t ♦r ♥r② ♣ t♦♥s t♦rt r♠♦rs ②♦♥ r rqr t ♥t♦ ♦♥tt tr♦♥tr♦♥ ♥trt♦♥ ②♦♥ ♥ ♥r②♥♣♥♥t ♥ ♦♣♦t♥t ♥r② ♣s r rr♥t② ♦♠♣t t r♥s ♥t♦♥ ♣♣r♦ ♦s ♦r t t♦♥ ♦ qs♣rt ♦rrt♦♥s t♦ ts ♦ t ♥r② t♦ rst♦rr ♥ ♣rtrt♦♥❬ ❪

①t stts r s♦ ♦t ♦ r ♦ ② r trt tr② t t♠♣♥♥t ♥st② ♥t♦♥ t♦r② ❬ ❪ ♦r ② ts♦t♦♥ ♦ t t♣tr qt♦♥ ♥ ♥ ♦♣t s♦r♣t♦♥ ts ♥ssr② t♦ t ♥t♦ ♦♥t t tr♦♥♦ ♥trt♦♥❬ ❪ s♠t♦s ♥♦♥tss r② ♦♥ ♦r ♦t♥♥ t r♦♥ stt ♥t♦♥s ♥ s ♦ t ♥r② r s tr s strt♥ ♣♦♥t ♦rt♦ t ② q♥tts t tr t♥s♦r

♥② t s ♥♦t ②t r tr t ♦♠♥t♦♥ ♠♥②♦②♠t♦s s ♦♥ r♥s ♥t♦♥s r s♥t ♥ ♠trs r tr♦♥ ♦rrt♦♥s r ♦ ♣r♠r② ♠♣♦rt♥ ♥ ♦①s t ♠t♣②

Page 66: Some ab initio tudies of the physical properties of materials

P ❯ ❨

♦♣ 3d ♦rts ②♥♠ ♠♥ t♦r② ♣rs♥ts ♥ tr♥t ♠t♦ t♦ ♠♦ t ♦rrt♦♥s❬❪ t s♦ ♥♦t ♦rtt ♦t sss ♦ ♠t♦s ♥ sss② ♣♣ t♦ t tr♦♥s♣tr♦s♦♣② ♦ ♥♠ ♦①❬ ❪

♥ sp ♦♥ ♠trs ♦r♦♥r s♦s r ①♣t t♦ r♦♥ stt ♣r♦♣rts sr ② s ♠t♦s r②st s②♠♠tr② ♦ s r♦♠♦r t t 3m s♣ r♦♣ t♦♠ strtr ♦♥ssts ♦ ♦♥ st♦rt ♦sr♦♥ ♣r ♣r♠t ♥t r ♥t② ♣s ♦♥ ♠tt♦♠ ♥ t♦♠ ♥t ♦sr♦♥ s t ♣① ♦ ♣♥t♦♥s ♣②r♠ ♦ r②st♦r♣ sts ♥ t ♦sr♦♥ r ♥ ② t ♥tr♦sr ♦♥♥♥ ♣♦r st p ♦♥ t♦♠ s ♥ ② ♦♥t t♦♥tr pp ♦♥ t♦ ♦♥t♦♠ ♥ t ♣♦r st ♦ ♥♦r♥ ♦sr♦♥ ♥ t s♦♥ st et qt♦r t♦♠ s ♦♥ t♦ t ♥♥ t♦♠ ♦ ♠tt♦♠ ♥tt ♥s ♥♦r♥ ♦sr ♥tr♦sr ♥ ♥ s♥t ♥ α♦r♦♥ ♥ ♠♦st ♦ t ♦sr s♦s tr s ♦♥ ♥ ♣r♥t ♥ ♥ t♦♠ s ♥ 12P2 ♥ 12s2 ♦r trt♦♠ ♥ ♦r♦♥ rs r

♥tr ♦ t ♦♥♥ ♠s ♦r♦♥r s♦s ② r♥t r♦♠r♥s ss ♦ ♠trs t t② r ♥♦♥tss ♦t♥ ♦♠♣r t♦ tr♦♥ ♥②❬❪ st♥♥ ♦♥ 12 11♦r 102 ♥tr str s ♥st s ♥ ♥♦t ♦♠♣r t♦r♥ r②sts❬ ❪ ♦♠♣rs♦♥ ♦ t rs♣t ♦♠♣rssts ♦ t ♥tr ♥ ♥trt♦♠ ♦♥s ② ♥t♦ ♠t♦s s ♣r♦ tt♥tr α♦r♦♥ ♥♦r ♦sr ♦r♦♥ r t ♦ r♦♥ ♦♥♥trt♦♥ 4 r ♠♦r r②sts tr ♦ t② ♦r♠ ♥ ♥rt♠♦r r②st ♥ t ♥tr♦sr ♦♥s ♦ str♦♥rt♥ t ♥tr♦sr ♦♥s❬ ❪ ♦sr ♦r♦♥r s♦s♦r♠ s♣ s ♦ ♦♥t ♠trs ♦♣t♥ ♥ ♥s strtr s ♦ t tr♦♥ ♥② tt s ♥tr♥s t♦ t ♦r♦♥ t♦♠

♦sr sp ♦♥♥ s ② r ♠♦r ♦♠♣① t♥ sp ♦♥♥ ♥♠♦♥ ♦r ♦tr ♦♥t ♠trs t ttrr ♦♦r♥t♦♥ ♥st② ♥t♦♥ t♦r② s ①♣t t♦ st t♦ ①♣♥ ♣②s♣r♦♣rts rt t♦ ts ♦♠♣① sp ♦♥♥

t♦♠ strtr ♦ 4 r♦♠ rst

♣r♥♣s

♥ ts st♦♥ ♦r ♠ s t♦ r t s ♥ sts ♦t tt♦♠ strtr ♦ 4 ② ♦♠♣r♥ ①♣r♠♥t t t♦ rsts ♦♠♣t r♦♠ rst ♣r♥♣s

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r t♦♠ strtr ♦ ♦sr ♦r♦♥ r r♦♠ ❬❪♥ st♦rt ♦sr r s♦♥ r♦♠♦r rs ttt♦rs ♥♦t s♦♥ ♥ ♦sr ♥trs s t♦♠s t t p

♣♦r st t r② s t♦♠s t t e qt♦r st r r②s t♦♠s t ♥ ♥tr ♥ ♥ ♥s P♦r t♦♠s r s♦♥ t♦ ♦♥ t♦ ♥♦r♥ ♦sr t ♦♥t t♦♥tr pp ♦♥sqt♦r t♦♠s r ♥ t♦ ♦♥ t♦♠ t t ♥ ♦ t trt♦♠ ♥

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t♦♠ strtr ♦ 123 4 ♦r♦♥ r ♦♥t♥s t♦♠s♥ ♦r ♦♣ r②st♦r♣ sts r ♦ sts ♦r♠ st♦rt ♦sr♦♥ t ♣♦r ♥ qt♦r sts t t♦♠s ♣r st tr ♥ ♦rt sts r rs♣t② t ♥tr ♦ t trt♦♠ ♥♦♥ t♦♠ ♥ t ♥ ♥s t♦ t♦♠s

①♣r♠♥t② t tr r♦♥ t♦♠s r t t♦ st♥s r♦♠t t ♦r♦♥ t♦♠s ♥ t sttr♥ ♥t ♦ 13 ♥s sr② ♦s t♦ t sttr♥ ♥t ♦ 11 ♥s ♥ ♦♥② ♣r♠trs ♥ ♠sr ② ♥tr♦♥ rt♦♥❬ ❪ t♦♠ ♣♦st♦♥s r♦♠ ❳r② rt♦♥ t ♥t tt t ♥ s ♥ tt♦♥ r♦♥ t♦♠ s ssttt ♥ t ♦sr♦♥❬ ❪ s t ❳r②♦r♠ t♦r ss Z 2 r Z s t t♦♠ ♥♠r t ♦r♠ t♦rs♦r t ♥♦r♥ ♠♥ts ♥ r r② ♦s ♥ t s tt♦ st♥s t♥ ♦r♦♥ ♥ r♦♥ t♦♠s ♥ t ♦sr♦♥ ♣tr ♣r♦ ② ❳r② rt♦♥ s t ♦♦♥ ♦♥ t tr r♦♥t♦♠ s sttst② ssttt ♦♥ ♦t ♣♦r ♥ qt♦r sts t ♣r♦♠♥♥ ♦r t ♣♦r st ♦r♠ s x1−x

p6y1−y e6 ♥

0.93 ≤ x ≤ 1 ♦r t ♣♦r st ♥ 0.74 ≤ y ≤ 0.86 ♦r t qt♦rst❬ ❪

♥ ♦rr t♦ ♥ ♥♦ ♦ t t♦♠ strtr ♦ ♦r♦♥ rt r♦♥ ♦♥♥trt♦♥ ♦ ♥stt sr strtr♠♦s t ♥t♦ ♠t♦s s ♦♥ t t ♣r♣♦s ♦ ♦♠♣r♥ r♦s ♦♠♣t ♣②s ♣r♦♣rts t ①♣r♠♥t tt♦♥s r ♣r♦r♠ t♥ s♥ t ♣♥ ♣s♦♣♦t♥t ♠t♦ ♦r ts ♥ ♦♥ ♥ s ❬ ❪

trtr ♠♦s

♥ ts sst♦♥ ♦r strtr ♠♦s r♦♥ ♦♥♥trt♦♥ ♥ ♦♥sst ♦ ♦♥ ♥t ♦ t♦♠s ♣r♦② r♣t ②tr♥st♦♥s ♦ t rs tt t♦rs ♥ ①♣t♦♥ s t bipolar

♠♦ ♦♥t♥s trt② t♦♠s t♦ ♣ t st♦♦♠tr② ♥ t polar rs♣ bipolar ♠♦ t ♥ s ♥ t ♦sr♦♥s ♦♥ rs♣ t♦ r♦♥ t♦♠s ♥ t ♣♦r st ♥ t equatorial

♠♦ t ♥ s ♥ ♦♥ r♦♥ t♦♠ s ssttt ♥ t qt♦r st ❲ s♦ ♥stt ♥t r t ♥ s ♥ t ♦sr♦♥ s ♠ ♦ ♣r ♦r♦♥ chain ♠♦ ♦r ♥tr♦s♦♠ s♦rr ♥ t ♥ ♠♥ t ♥st ♦ disordered

chain ♠♦ st ♠♦ ♦♥ssts ♦ r ♥ rich chain

♠♦

ssttt♦♥ ♦ r♦♥ t♦♠ ♥ t ♣♦r st ♦ t ♦sr♦rs s① ♣♦ssts rst♥ ♥ ssttt♦♥ s♦rr s ♠s t

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♦sr s②♠♠tr② ♦ t ♥t ♦♥ r r♦♠♦r ♥ ♦r t♦♥s ♦ ♥♦t t ①♣t② t ssttt♦♥ s♦rr ♥t♦ ♦♥t st♦♦ r s♣rs ♦ rqr r♦r t ♣r♦ r♣tt♦♥ ♦ r♦♥ t♦♠ t ♥ ♣♦st♦♥ ♥ t ♦sr♦♥ ♥s s♠ st♦rt♦♥ r♦♠ t r♦♠♦r s②♠♠tr② t♦ s♥tr ♠♦♥♦♥ ❲ tt ts ♣♣r♦①♠t♦♥ ♦s ♥♦t ♠♦② t ♦♥s♦♥s♦ ts ♣♣r

t♦t ♥r②

t♦t ♥r② ♦t♥ t♥ s r♣♦rt ♥ strtr t t ♦st ♥r② s t polar ♠♦ ❲ t ts ♥r② s♦r rr♥ bipolar ♠♦ ♦♠s s♦♥ t ♥ ♥r② r ② ❱ ♣r r♦♥ t♦♠ ♥ s ♥r② r♥ s r② s♥♥t♥ ♦rrs♣♦♥s ♥ tr♠s ♦ tr♠ ♥r② t♦ t♠♣rtr r t♥ rtr♠♦r t ♥rts ♦s t ①s♦♥ ♦ t qt♦r ♠♦ t chain ♠♦ t disordered chain ♠♦ ♥ t richchain ♠♦ t s♦s tt t ♥ s ①s♦♥ ♦ t equatorial

♥ chain ♠♦s rtr ♦♥r♠ ② ♥s♣t♥ t tt ②♥♠s ♥ t s♣tr ♦r♦r t s ♦ t ♦r♠t♦♥ ♥r② ♦disordered chain ♥ rich chain ♠♦s s♦ tt ts ♠♦s r ♥st r♦s ♥ rs♣t②

r♥ ♥ t♦t ♥r② t♥ ♦r r♦s strtr ♠♦ss ♠ ♠♦r ♠♣♦rt♥t t♥ t r② ♦ ①♥ ♥ ♦rrt♦♥♥t♦♥s ttr s ♥ ♠t t♦ ♠♦ ♠❱t♦♠❬❪s ♦r ♠♦s r ♦♥② ② t ♦t♦♥ ♦ ♦♥ r♦♥ t♦♠ t ①♥♦rrt♦♥ ♥t♦♥ ♠ts t r② ♦ ♦r t♦♥s t♦ ♠❱ ♣rr♦♥ t♦♠ ♥ r②st ♣ss r♥ ② ss t♥ tt ♠♦♥t ♥r② st♥s ♥ ts ♠② t♦ r♦♥ ♣rt♦♥ ♦ t ♠♦stst ♣s ❲ s tt ts s ♥♦t t s ♥

rtr♠♦r t r♥ ♥ t♦t ♥r② t♥ ♦r strtr ♠♦s s s♠r ♥ ♥ ♥ ♥♦t s♦♥ ❬❪ t♥ ♠❱♣r ♥ ♦ r♦♥ t♦♠ s s s ♦♥♥ ♥ t ♣rtt② ♦ t ♥rts ♦r ♦r ♠♦s ❲ ♠♣s③ tt ♥ t s♠ ♣②s ♦♥t♥t ♦♥tss ♥♦t tt ②♦♥strt♦♥ tr s ♥t♦♥ ♦ rr♦rs t♥ t ①♥ ♥r②♥ t ♦rrt♦♥ ♥r② ♥ s ♥t♦♥ s ♥♦t t♥ ♥ t ♥t♦♥s❬❪ ♠s t ♦♠♣tt♦♥s ♦t ♥ ♥ ♥ ♦rt ♣r♦r♠♥ ♥ ♦♠♣r♥ ♦r♦r ② ♦♥strt♦♥ ♥t♦♥s t♥ t♦ rs t ♥r② ♦ t ss ♥s ♣s ♥ ♥t♦ ♦r tr stt②❬❪ r♦r t s ♥trst♥ t♦ ♦♠♣t ♥r②r♥s ♦t ♥ ♥ ♥ ♦rr t♦ ♦t♥ ♥ rr♦r r ♥t r②st ♥st② rs ♠♦♥ t ♣♦②♠♦r♣s s r♥s ♥ t♦♥strt♦♥ ♦ t ♥t♦♥s ♦ ♥♦t ♠♦② t rt stts ♦ ♦r

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♦t ♥r② ❱ ♣r ♥ ♦ r♦♥ t♦♠ ♦t♦♥ trs♣t t♦ t polar ♠♦ t♥ r♦♠ ❬ ❪

♦ ♥ ♦sr♦♥ ♦t ♥r② ❱Polar 11p Bipolar 2 102

p 12 Equatorial 11e Chain 12 Disordered chain 11p rich chain 102

p

strtr ♠♦s ♥ ❬❪

r rsts ♦r 4 r r♦st ♥st ♣♣r♦①♠t♦♥s ♦♥trst♥②rt s ♦ t ♥r② ♦ r♥t r②st strtrs ♦ ♣r r♦♥♦r ♦ ♣r ♦r♦♥ r ♠ ss r♦st r♣t s ♦♥ ♠♦r st t♥♠♦♥ ② ♠❱t♦♠ ♥ ❬❪ rs ♠♦♥ s ♦♥♠♦r st t♥ r♣t ♥ ② ♦♥② ♠❱❬❪ ❩r♦♣♦♥t♠♦t♦♥ ♠t rrs t ♠♦st st ♣s r② t tr♠♥t♦♥♦ t stt② ♦ ♣r r♦♥ ♣♦②♠♦r♣s s ②♦♥ t ♣t② ♦ t ①♥ ♥ ♦rrt♦♥ ♥t♦♥s❬❪ s s ♣rtr② tr ♦rr♣t s ❱♥ r ❲s ♥trt♦♥s r ♥♦t ♣r♦♣r② t♥ ♥t♦♦♥t ♥ ♥♦r ♥ ❬❪

r♥♥ t♦ ♦r♦♥ ♥ t♦♥s ♦r ♣rt r②sts α12 s ♥s♦♥ t♦ ♠♦r st t♥ ♣rt t♦♠sβ♦r♦♥ ♥ ❬❪♥t t♦♥s ♣r♦r♠ t ♥sr s♠♣♥ ♦ t r♦♥ ③♦♥♦ α♦r♦♥ ② t♦t ♥r② r♥ t♥ α ♥ β♦r♦♥ ♦ ♠❱ ♣r t♦♠ ♥ ♥ ♦ ♠❱ ♣r t♦♠ ♥ ♦t ♣rt♥tt α12 s ♠♦r st❬❪ r♥ t♥ ♥ sr② ♠♣♦rt♥t ♥ ts s ♠❱ ♣r t♦♠ ♥r② r♥ ②s♥ rr♦r r ♦ t ①♥ ♥ ♦rrt♦♥ ♥t♦♥s

♥ t ♦tr ♥ t♦♥s ♥♥ ts ♣rt tt tβ♦r♦♥ s t ♠♦st st ♣s❬ ❪ ♥r② r♥ trs♣t t♦ ♣rt α♦r♦♥ s t ♠♦st ♠❱t♦♠ r ♦ t ♦♠♥t♦♥ rr♦r r ♦ ♠❱ s♦ ♥ ts s t♦♥s r t♠t ♦ ①♥ ♥ ♦rrt♦♥ r② ❲ tt t t♦rttr♠♥t♦♥ ♦ t stt② ♦ ♣r r♦♥ ♦r ♣r ♦r♦♥ ♣♦②♠♦r♣s srs rtr t♦rt rtr♦s t♦ ♦r♦♠ t ♥tr♥s ♠tt♦♥♦ ♥ ♥t♦♥s

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tt ②♥♠s

r♥♥ t♦ tt ②♥♠s ♦♠♣t ❬❪ t ♣♦♥♦♥ rq♥st t ♥tr ♦ t r♦♥ ③♦♥ ♦r t polar equatorial ♥ chain ♠♦s ❲ ♥♦t tt ♥ ♦r s t tr♦♥ strtr ♥ t tt ②♥♠s r ♣r♦r♠ t♥ t s♠ t♦rt r♠♦r s♠♣s tt ♥s ♥ ♦t rtr ♣♦t♥t ♥ ♥ ①♥ ♥ ♦rrt♦♥ ♣♦t♥t r t t♦ rst♦rr ♥ ♣rtrt♦♥ t♦r② srs♣♦♥s ♦ t sr♥♥ ♣♦t♥t t♦ t ♣rtr♥ ♣♦♥♦♥ s ♦♠♣ts♦♥sst♥t② s♦ tt t r♥ t s♠♠♣r ♠♦s t tr♦♥ ♥st② ♦s ♥♦t r② st t t t♦♠ ♠♦t♦♥ ♦♠♣r t♦ ♥♦r ♠♦s ♦r ♦♠♣tt♦♥ s♠ ♦r ♣♦♥♦♥ rq♥s ♥ s♣♠♥t ♣ttr♥s ♦s ♥♦t ♦♥t♥ ♥② tt♥ ♣r♠tr

♥ r r♣♦rt t t♦rt s♣tr♠ ❬❪ ♦r ♥rr s♦r♣t♦♥ ♦♠♣r t t r♦♠ ❬❪ P ♣♦st♦♥s r r② ♥ttr r♠♥t ♦r t polar ♠♦ ❲t rs♣t t♦ t equatorial ♠♦ts s ♣rtr② tr ♦r t ♠♦ ♦sr ♥r ♠−1 s s rt♦♥ ♦ t ♥♥tr t♦♠ ♣r♣♥r t♦ t ♥ ①s

sr♣♥② t♥ ①♣r♠♥t ♣ ♣♦st♦♥s ♥ chain ♠♦♦♥s s ♥ ♠♦r ♣r♦♥♦♥ t rq♥s ♣ ♦srr♦♥ ♠−1 ♦♠s r♦♠ t strt♥ ♦ t ♥ ♥ t ♥♥ t♦♠s rt ♥ts②♠♠tr② ungerade rt♦♥ rq♥②s ② r rr ♥ t ♥ s P♥ t♥ ♥ t ♥ s P♥s ♥ ❲ tr♦r ♦♥ tt t chain ♠♦ ♥ srr strt♥ ♦ ♥s ♦s ♥♦t ♦r ♥ ♠sr♥rr s♣tr

r♥♥ t♦ ♣ ♥t♥sts ♥ t polar ♠♦ s♦ ♥ ♣♥ t t ♦♥ s♥ ♣r♠tr ♥ t ♣r♦♣♦rt♦♥ t♥ u ♥ 2u

♣♦r③t♦♥s ♥ ts ♣r♦♣♦rt♦♥ ♦ ♣♦r③t♦♥s s ♥♥♦♥ ♥ ①♣r♠♥t r t s ♥ stst♦r② r♠♥t t ①♣r♠♥t s♦♥ ttt t♥s♦r ♦ t rs s ♣r♦♣r② ♦♥t ♦r ♥ t t♦♥s

♥♦t s♥t rt♦♥ ♥ 4 s ♦sr tr ♥ ♠♥ s♦♥ ♦r♥ ♥rr s♦r♣t♦♥ s s s t ♥tr ♦ t ♦sr♦♥ s ♥♥rs♦♥ ♥tr ♣rt② ♦ ♠♦ t rs♣t t♦ t ♥rs♦♥ ♥tr s♥q ♥ t ♠♦ s tr ♥rr t ♥r u ♥ 2u ♠♦s♦r ♠♥ t r g ♥ 1g ♠♦s r♦r t s ♥trst♥ t♦♦♠♣r ♦r ♦♠♣t ♣♦♥♦♥ rq♥s s♦ t♦ t ♣s ♦sr ②♠♥ sttr♥ ♦ ♦r ♥♦ ♦♥② ♦♥ ♠♥ s♣tr♠ ♠sr♦♥ s♥ r②st s ♥ r♣♦rt ♥ t trtr ♥ t s ♦r rr♥♥ r sr ♣s r r♦♥ ② s♦rr ♥ ♥ t rq♥② r♥ t t♦rt rq♥s ♦ ♦r ♠♦s ❬❪ ♦♥t t ①♣r♠♥t

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r ♥rr s♣tr♠ ♦ 4 r♦♠ ❬❪ s ♥ ①♣r♠♥t❬❪ ♦ ♥ t♦rt s♣tr♠ ♦r t chain ♠♦ ♣♥ equatorial ♠♦ ♣♥ polar ♠♦ ♣♥ P♥ s♣tr♠♦r t polar ♠♦ r t ♣r♦♣♦rt♦♥ ♦ u ♥ 2u ♣♦r③t♦♥s s♥ tt t ♦♥ s♥ ♣r♠tr t♦ r♣r♦ t ♥♥♦♥ ♠①tr♦ ♣♦r③t♦♥s ♥ t ①♣r♠♥t s t①t

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♦♥tss t♦ rt♦♥ ♠♦s t ♠−1 ♥ ♠−1 ♥ s♥ ♦t ♦t ♠♦s ♥♦ ♦♥ ♥♥ ♠♦ ♦sr t ♠−1 ♦rrs♣♦♥s ♥ ♦r t♦♥s t♦ r♦tt♦♥ ♦ t ♥♥ t♦♠sr♦♥ t ♥♥tr ♠♦ ♦sr t ♠−1 ♦rrs♣♦♥s t♦t rt♦♥ ♦ t ♦sr♦♥ s ♠♦ s ♥ ♣r♦s② ♦sr♥ α♦r♦♥ ♥ t s s♦♥ t♦ str♦♥② r♠♦♥❬❪

♦♠♣r t t s♦rr♥ r♦♥♥ ♦ ♦tr rt♦♥s ts♠ ts ♦ t t♦ ♣s ♥t tt t t♦ ♦ ♠♥t♦♥ ♠♦sr r♠♦♥ ♥ ♦r♦♥ r rq♥② r♥ t♥ t♠ str♦r q♥tt② s ①♣t t♦ r♣r♦ ♥ ♦r t♦♥s t♥ t r♠♦♥ ♣♣r♦①♠t♦♥ r s♦s tt t①♣r♠♥t rq♥② r♥ s r♣r♦ ♦♥② ② t polar ♠♦s r♥ s s♠r ② t♦r ♦ ♥ t equatorial ♠♦ r♦rt equatorial ♠♦ ♥ srr s ♣♦ss strtr ♠♦ ♦r4

st t ♥♦t st ♥♦t tt ♦r t♦♥s s♦ ♥♦ rt♦♥♠♦s ♦ ♠−1 r ♠♥ ♣s r ♦sr♦ ♠−1 ♥ ♠♦st ♦ t ①♣r♠♥ts ❬❪ ♦♠ r♦♠ t ♦ tst♦♥ rs ♦r ♠♥ sttr♥❬❪ ω s t ♣♦♥♦♥ rq♥② t♥t♥st② ss ω4 ♣♦r t ♦ rq♥② s t s♥tr♦ ♥st② ♦ stts ♦ ♦st ♣♦♥♦♥s s ♣♦♥♦♥s ♦ s t♦ t s♠♣s ♥st strtr s♦rr t② r ①♣t t♦ ♥s♥ ♥ s♠♣s

r ♥t s♦♥♥

♥ t ♣r♦s sst♦♥ t ♦♠♣rs♦♥ ♦ t t tt ②♥♠s t ①♣r♠♥t ♦ s t♦ ♥t② t t♦♠ strtr ♦ 4 s ♥ ♥ 11p ♦sr♦♥ t t r♦♥ t♦♠ ssttt ♥t ♣♦r st t s♦ s♥ tt ①♣r♠♥t rt♦♥ s♣tr♦ s♦ r r♦♥♥ s ② ssttt♦♥ s♦rr ♥♦r strtr ts r♦r t♦ ♦♠♣t s♣tr tt ♠ ♦ r♥♥ ♠♦r ♦t ts ts❬❪

r s ♦ t ♠ st ♦ 13 ♥ r♣♦rt ♥ t ①♣r♠♥t trtr ①♣r♠♥ts ❬❪ r t ♦♥♥♦tr ♦t t♦ s♥s r♦♥ ♥ ♣♣♠ ♥② ♦♥ ①♣r♠♥t♦r r♣♦rts s♥ t ♣♣♠❬❪ ❲ ♥♦t tt ts ①♣r♠♥t ②t st rs♦ s♣tr♠ s t♦♥ ♣ ♠② s♦ ①♣♥ ② r♥t r♦t ♦ s②♥tss ♦ t s♠♣ ②♥ ♠♦r strtr s♦rr

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r ♠♥ s♣tr♠ ♦ 4 r♦♠ ❬❪ ❯♣♣r ♣♥ ①♣r♠♥t❬❪ ♦r ♣♥ t♦r② ♦r chain polar ♥ equatorial ♠♦s♥ s♣♥s ♥ rs♣t② ♦ ♥ g ♠♦ s ♥ 1g ♠♦

r t♦♥s s♦ tt t polar ♥ bipolar ♠♦s ①♣♥ t①♣r♠♥t s♥s r② Ps r♦♥ ♥ ♣♣♠ ♦♠ r♦♠♥♥ r♦♥ t♦♠s ♥ r♦♠ r♦♥ t♦♠s ♥ t ♣♦r sts ♦ t♦sr rs♣t② polar ♠♦ bipolar ♠♦ ♦s s t♦ ①♣♥ t s♥ t ♣♣♠ ♦sr ♥ ❬❪ ♦♠s r♦♠ r♥t sr♥♥ ♦ t ♠♥t ♥ t♦ r♦♥ t♦♠s r ssttt ♥ t s♠ ♦sr♦♥ r♦♠ t ♣♦♥t ♦ ♦ t t♦t ♥r②t ♦rt rt ♦t♦♥ ♦ t♦ r♦♥ t♦♠s s ♥ ♥t♣♦ ♣♦r♣♦st♦♥s❬❪ rtr♠♦r ♥♦t tt ♣r♥ts ♦ ♣r 12 ♦sr r ♥ssr② t♦ ♣ t st♦♦♠tr② ♥ ♦r t♦♥s

r♥♥ t♦ t equatorial ♠♦ t t ♦ t ♣ ♣rt ② tt♦r② tt ♦♠s r♦♠ ♥♥ r♦♥ t♦♠s s rtr t♥ ♣♣♠ s s s♥♥t② rr t♥ ♥ t ①♣r♠♥t ♦r♦rt t s♣tr♠ ♦ t 11 ♥s s s♦r ♦♥ t s ♦♥t ♠ sts ♦r t equatorial ♠♦ r t r♥t ts ♥♥ t ♦sr s♣tr♠ s♦s s♦r ♦♥ t s ♦♣♦st ♠ sts ♥ r♠♥t t t polar ♠♦❬❪ s

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♦ s t♦ srr t ssttt♦♥ ♦ ♦♥ r♦♥ t♦♠ ♥ t qt♦rst s ♣♦ss strtr ♥rts rt♦♥ ♥ s♣tr tsr ♦♥ ts ♣♦♥t

rtr♠♦r r♦♥ t♦♠ t t ♥tr ♦ t ♥ ♦ ② ♠ st s r s ♣♣♠ ♥ t 13 s♣tr♠ s♥ s♥♦t ♦sr ♥rts rt♦♥ ♥ s♣tr r♦♥ t t tt ♥♦ ♥s r ♣rs♥t

♥② ♦♠♣rs♦♥ ♦ ♦♠♣t ♥ ♦sr s♣tr ♦s st♦ r t ♦♥s♦♥ tt t t♦♠ strtr ♦ 4 ♦♥ssts ♦ ♥ ♥ 11p ♦sr♦♥ t ♦♥ r♦♥ t♦♠ ssttt ♥t ♣♦r st ♣r♥ts ♦ t ♦sr 10

p2 ♦r 12

t♦♠ strtr ❲ st♠t tt ♦ t ♦sr r 11p r 102 ♥ r 12 ♦♥s❬❪

4 13C ♠ sts δTMS ♣♣♠ ♥ t ♦rrs♣♦♥♥ ♣ ♥t♥sts ♥ rts ①♣r♠♥ts r♦♠ ❬❪♦t tt t rs♦♥♥ t ♣♣♠ s s ♦♥② ♥ t ①♣r♠♥t♦ ❬❪ ♦r② ♠♦s s ♥

①♣r♠♥ts ♦r② ❬❪ ❬❪ ❬❪ Bipolar Polar Equatorial Chain

± ♠♦s ± s tr ♠♦s

♦♥s♦♥s

♥s♣t♦♥ ♦ ♦t ♥ rt♦♥ s♣tr ②s t s♠ ♣tr ♦rt t♦♠ strtr ♦ 4 ♥ ♥ 11p ♦sr♦♥ t♦♥ r♦♥ t♦♠ ssttt ♥ t ♣♦r st

r s ♥♦ s♥ ♦ t s♥tr ♦ t♦♠ t t ♥ ♥tr ss ♠♣♦rt♥t ♦♥sq♥s ♥s ♥ ♥♦t rs♣♦♥s ♦r t♦r♦♥ r ♠♦r♣③t♦♥ ♥ s♦ ①♣r♠♥ts❬❪

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r 4 11B ♠ st s♣tr♠ ①♣r♠♥t t sr♦♠ ❬❪ ♥ t♦r② ♦r t polar equatorial ♥ chain ♠♦s r♦♠ ❬❪

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P ❯

st② 10p2 ♦sr r ♣rs♥t s ts ♥ s♦♠ 4 s♠♣s

❲ st♠t tt ♦ t ♦sr r 10p2 s ts

♥ ①♣r♠♥t② ♦sr ♣rs♥ ♦ 12 ♦sr s ♥rr ② s r♦♠ t ♦sr st♦♦♠tr② ♦ ♦r ♥♦ tr r♥♦ rt ♦srt♦♥s ♦ 12 ♦sr ♥ 4 s♠♣s

t♦♠ strtr ♦ ♦r♦♥ rs t

♦r r♦♥ ♦♥♥trt♦♥s

t r♥ t t s ♦ 4 ♥♦ ♦t ♦r♦♥ rs t ♦rr♦♥ ♦♥♥trt♦♥s ♠st ♠♣r♦ ♦t ①♣r♠♥t② ♥ t♦rt② t♦♠ strtrs r ♥♦t ♥rst♦♦ ♥♦r r t ♣sstts❬❪

❲ ♦♠♣t t qr♠ ♦♠ ♥ ♦r♠t♦♥ ♥r② ♦sr strtr ♠♦s t♦♥s r ♣r♦r♠ t♥ s♥t ♣♥ ♣s♦♣♦t♥t ♠t♦ ①♥ ♥ ♦rrt♦♥ ♥r②s ♦♠♣t ♥ t ♦ ♥st② ♣♣r♦①♠t♦♥ ♣s♦♣♦t♥ts ♦♦r♦♥ ♥ r♦♥ r ♦♣ t t r♦rrt♥ s♠❬❪♦r ♦r♦♥ rs ♦r♦♥ ♥ ♠♦♥ ♣♥ s ♣ t♦ ♥t t♦♦ ② ♥ ♥ ♥ t ss st rr ♦t r♦♥ ③♦♥ s ♥ s♠♣ t ♣♦♥ts ♥ t ♥t s♠♦♥♦♥ ♦r♦♥ rs t r♦♥ t♦♠s ♥ t ♦sr ♥ ♣♦♥ts ♥ t ♥t s r♦♠♦r e.g . ♦r α♦r♦♥ ♦r ♦r♦♥ rs t 12 ♦sr ♦r ♠♦♥ ♣r♠trs ♥ t♦♠rs ♦ r♦♠ ♥ r① t♦ ♠♥♠③ t t♦t ♥r② t tt♦rt qr♠

♦r♠t♦♥ ♥r②

♦♦♥ ♣rs♥t ♥♦ α♦r♦♥ rs♣ ♠♦♥ s t ♠♦st st♣♦②♠♦r♣ ♦ ♣r ♦r♦♥ rs♣ r♦♥ t♥ ♦r tr♣ss s sst♦♥ rst② s ♦ t ♦r♠t♦♥ ♥r② ♦♦r♦♥ rs ♥ ♦♠♣t ♦r ♦r♠t♦♥ r♦♠ α♦r♦♥ + ♠♦♥

❲ rst ♦♥sr strtr ♠♦ s st t ♥ ts ♦r♠t♦♥ ♥r② E f s ♥t t rs♣t t♦ ♦♠♣♦st♦♥ ♥t♦ α♦r♦♥ +♠♦♥ ♥ ♥ E f s t s♠st ♦♥ ♠♦♥ strtrs t t s♠r♦♥ ♦♥♥trt♦♥ ♠♦♥ ♠♥② strtr ♠♦s tt ♥ ♥stt ♦♥② t ♠♦s ♦ r ♦♥ st❬❪ t r♦♥ ♦♥♥trt♦♥ t polar ♠♦ 4p s t ♦st ♦r♠t♦♥ ♥r② t ♣♣r♦①♠t② r♦♥ ♦♥♥trt♦♥ 132 s t ♠♦st

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st ♣s t ♦♥ssts ♦ ♦♥ 12 ♦sr♦♥ ♥ ♦♥ ♥ ♠♦ ♦♠♥♥ ♦t 4p ♥ 132 ♦♥ t ♥t s s♦ st t

♦♥② tst ♦r strtr ♠♦s ♥st ♦♠♣♦st♦♥ ♥t♦ 4p + α♦r♦♥ ♦r r♦♥ ♦♥♥trt♦♥ ♦r t♥ ♦r4p + ♠♦♥ ♦r r♦♥ ♦♥♥trt♦♥ rtr t♥ r♣rs♥② ♥♦ ♣ss ♥ ♦♥ st ♥st ts ♦♠♣♦st♦♥ ♥ ♦r 132 ♦♥ E f

B4C ♠❱ ♣r t♦♠ r rst s s♠r t♦

♣r♦s t♦♥s ♠❱t♦♠ t ♥ ♠❱t♦♠ t ♠♥tt♠♣rtr❬❪ ♠♦ ♦♠♥♥ 4p ♥ 132 s s♦ ♠r♥②♥st f

B4C ♠❱t♦♠ s ♥♠rs r ♦r

t♥ r② ♦ t ①♥ ♥ ♦rrt♦♥ ♥t♦♥s s sst♦♥

♣♥ t ♥♥tr t♦♠ ② ♥② ♥ 4p ♦r ♥ 132 ②st♦ ♠♦s t ♦r r♦♥ ♦♥♥trt♦♥ rs♣t② sr②sts t ♥s r ♦♥ t♦ ♥t ♦r♠t♦♥ ♥r② trs♣t t♦ ♦r♠t♦♥ r♦♠ α♦r♦♥ + ♠♦♥ ② ♦r ♣♦st ♦r♠t♦♥ ♥r② ♥ ♥ s♦ ♦♠♣♦s♥t♦ 4p + α♦r♦♥ ♦r 4p + ♠♦♥ ♥ tr♠♦②♥♠ ♦♥t♦♥s

♥ ♦♥s♦♥ ♦♥② 4p s ♦♥ t♦ tr♠♦②♥♠② st ♥♦r t♦♥s ♦r ♦tr ♣ss r ♦♥ tr♠♦②♥♠② ♥st♥r ♠♥t ♦♥t♦♥s s t t② r ♥rt② ♦st♦ ♦♠♣♦st♦♥ ♥t♦ 4p + α♦r♦♥ ♦r 4p + ♠♦♥ ♥tr♦♣② ts r ①♣t t♦ rtr ♦r ts ♦♠♣♦st♦♥ t ♥♠♥t t♠♣rtr ♥ ♦r ♥t s ♦ t ♦r♠t♦♥ ♥r② t rs♣t t♦ α♦r♦♥ + ♠♦♥ t ♦r ♣ss ♦♥♦♥tss ①st tr ♥ ♠tst stt ♠♦♥ ♦s ♦r s ts ♥ ♥ ♦trs ♣rt r②st ♦ 4p s 10

p2 ♦s s sst♦♥

r♥♥ t♦ ♥st strtrs❬❪ ♦r s ♦ t ♦r♠t♦♥ ♥r②t rs♣t t♦ α♦r♦♥ + ♠♦♥ r tr ♥ t♦tr t♣r♦s sts❬ ❪ ♦♥ ♥ ♦r♠t♦♥ ♥r② tr 4p s t ♠♦st st ♣s ♦♠ ♦t ♦r ♠♦s ♦r ssttt♦♥ s♦rrr♦ ♥ t bipolar ♠♦ r♦ ❲ ♥rr r♦♠ t r♦♥♥ ♦ t ①♣r♠♥t rt♦♥ ♠♦s tt ssttt♦♥ s♦rrs ♣rs♥t ♥ ♥s♣t♦♥ ♦ t ts s tt t bipolar ♠♦ s♦sr s t ♥ t s♠♣s ❲ ♥♦ ♦♠♣r ts t♦ ♠♦sr rst ♣♣r♦ t♦ ♦♥t ♦r t t ♦ ssttt♦♥ s♦rr r♦ s t♦ ♦ t ♥ t♦ ssttt t r♦♥ t♦♠ ♦t s♦♥ ♦sr♦♥ t r♥t ♦t♦♥s ♥ t ♣♦r st t ♦s ssttt♦♥ s♦rr ♦♥ t ♦r♠t♦♥ ♥r② s ♥♦t r♦ ♥ t strt♥ r♦♠ t♦ ♥t ♦sr 11p 11p ♦♥ ♦

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①♣t tt t t ♦♥ t ♦r♠t♦♥ ♥r② ♦ ①♥♥ ♦♥ r♦♥t♦♠ ♥ ♦♥ ♦r♦♥ t♦♠ ♥ t s♠ ♦sr♦♥ rst♥ ♥ ♥♦♥ ♥t 11p 11p′

r♦ s♦ ♠ s♠r t♥ tt ♦ bipolar

♠♦ r ♦♥ r♦♥ t♦♠ ♥ ♦♥ ♦r♦♥ t♦♠ r ①♥ t♥t♦ ♥♦r♥ ♦sr ②♥ 10

p2 12 r♦ ♦r ts s

♥♦t t s t♦ ♠♦s ♦♠♣r ♦r♠t♦♥ ♥r② r♦s ♥ ❲ t♥ ♦♥ tt tr ♦r st② ♦ ssttt♦♥ s♦rr s ♦♥r♥ t rs♣t t♦ t ♥♠r ♦ ♥t s♥ tt rr s s♦ st ♦r tt ssttt♦♥ s♦rr ♠t ♥rt② ss ♦r t♥ ♦ ssttt♦♥ ♥ t ♦sr♦♥

t r♦♥ ♦♥♥trt♦♥ ♦ ♦♥ ♥t s ♦ t ♥r② ♦r t equatorial ♥ chain ♠♦s ♣r♦s② sss ♥ sst♦♥ r♦s ♥ ♦♥tss ts ♠♦s ♠r ♦r♠t♦♥ ♥r② t♥ t bipolar ♠♦ s ♦♥sst♥t tt t tt ♥s♣t♦♥ ♦ s♣tr♦s♦♣ t ♥s s t♦ ① t♠♦r♦r ♦♥ ♣♦st ♦r♠t♦♥ ♥r② ♦r t disordered chain ♥rich chain ♠♦s ♦s t♦ ① tr ♦r♠t♦♥ ♥ t ♦♠♣♦♥s r♦s ♥

t r♦♥ ♦♥♥trt♦♥s ♦tr t♥ ♦r ♥st ♠♦s s♦ ♣♦st ♥r② ♦ ♦r♠t♦♥ rr t♥ ♦r ①♣t r② ♦♥ ①♥ ♥ ♦rrt♦♥ ♥t♦♥s s sst♦♥ ② ♥ ♥♦t ♣r♦ ♥ ♠tst stt ♦r s ts ♦r ♥st♥ ♥srt♦♥♦ r♦♥ t♦♠s ♥ ♥trstt r②st♦r♣ sts s ♣r♦ t♦ ♥ ♥♣♣r♦♣rt ② ♦ ♠♦♥ ♦r♦♥r ♦r♦♥ rs r♦s ♥ ♥♦tr ♠♦ s ♥ sss ♥ t s♥t trtr♦♥t♥s ♦♥ t♦♠ t t ♥tr ♦ t ♦sr♦♥❬❪ ♠♦ s r② ♣♦st ♦r♠t♦♥ ♥r② r♦s ♥ r♦r ♦ ♥♦t ①♣t t♦ ♦sr ♠trs ♥ ♦r♦♥ ♦sr ♦♠♠♦t ♦♥ t♦♠ t t ♦sr♦♥ ♥tr

sss♦♥

4 ♦r♦♥ rs t ♦ r♦♥ ♦♥♥trt♦♥s ♣r♦② r ♠①trs ♦ r♦s ♥ ♦s t r♦♥ ♦♥♥trt♦♥ ♦tr t♥ t ♥♠r♦s strtr ♠♦s ♦ ♥ srr s ♣♦ss ♥ts ♥st ♠♦s ♦ r s s t♦rs tr♠♥t♦♥ ♦ t t♦♠ strtrs ♦♠♠♦♥ t♦t tt ♥tr♥s strtr ts ♦r♥t r♦♠ t ♥rt② ♠♦r ♦r ♦♥rt♦♥ ♦♠♣r t♦ t strtrs❬❪ s t♦rtstt♦♥ ♥ t sr♣rs ♦♠s r♦♠ t s♠ ♥♠r ♦ ♣♦ss ♥ts rtr♠♦r t ♦♠♣tt♦♥ ♦ t ♦r♠t♦♥♥r② s♦s tt ts strtrs r ♥♦t st t rs♣t t♦ ♦♠♣♦st♦♥ ♥t♦ 4p ♦r♦♥ r + α♦r♦♥ ♦r 4p + ♠♦♥

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s ♠tstt② ①♣♥s ② ♣②s ♣r♦♣rts ♠sr ♦♥ r♥t s♠♣s str♦♥② ♣♥ ♦♥ t s②♥tss r♦t ♦r ♣rs② t♥stt② ♦ 132 t rs♣t t♦ ♦♠♣♦st♦♥ ♥t♦ 4p + α♦r♦♥s♦ ①♣♥s t ♦ ♥ t r♦t t♦ s②♥ts③ s♥ r②sts ♦132❬❪ ♥stt♦♥ t ♥t♦ ♠t♦s ♦ ♥ ♥t st③t♦♥ ♥r ♣rssr s♦ s s♦♠ t ♦♥ ts qst♦♥

t s r② ♥ ♦r ♦r♦♥ rs t ♦ r♦♥ ♦♥♥trt♦♥s ♦ ♦r ♥♦ ♦♥② t ①♣r♠♥t ♦ ❬❪ ② t♦♥ ♦r♦♥ rs t ♥ r♦♥ ♦♥♥trt♦♥s s ①♣r♠♥t s♦ t♦ t♦♥ s♥s s t♦s ♦ 4p ♥t♥sts ♦ts t♦♥ ♣s ♦r r② r② t♥ ♥ t♦♠r♦♥ ♦♥♥trt♦♥s s♦ tt ♦♥ ♥ ♥♦t s♠♣② ♦♥sr t♠ s ♥r♣r♥ts ♦ ♦r♦♥r ♦r♦♥ rs ♣rs♦♥ ♦ t t♥qs rst② ♥rs s♥ ♥ t ♦ ♦ t♠♦st ♠♣♦rt♥t♦ ♣r♦r♠ ♥ ①♣r♠♥ts ♦♥ ♦r♦♥ rs s ♠t♦s r♠tr ♥♦ t♦ ♣ t ♥rst♥♥ ♦ ts ①♣r♠♥ts

♥② ♦♥ s♦ ♥♦t tt tr ♠♦s ♦ ♦♥t♥ ♥ ♦♥♠r ♦ tr♦♥s ♣r ♥t ♥ ♥ r ♠ts ♥ ♥② ♥ t♦r②♦♥trst♥② ♦r♦♥ rs r t♦t t♦ s♠♦♥t♦rs❬❪ ❲t♥ tt t ①♣r♠♥t ♥♦ ♠t t♦♦ s♠♣ ♣♥♥t ♣rs ♠sr♠♥t ♦ t rsstt② ♦♥ ♥ s♠♣s s ♥ ♥♦ r② ♣ ♥ sr♠♥t♥ ♠♦♥ t ♠♦s ♦ ❲s♦ ♥ t ♥①t st♦♥ tt t str♥t ♦ t tr♦♥♣♦♥♦♥ ♦♣♥♦♠♥ t t r rt♦♥ rq♥② ♠s ♦r♦♥ rsr② ♥trst♥ ♠t stt ♥

tr♥t ♦ t tr♦♥♣♦♥♦♥ ♦♣♥

♠♦♥ ♣♦ss ♥ts ♦r t r♦ ♦ t ♠♥ ♥ ♦ ♦r ♦r♦♥rs t ♦ r♦♥ ♦♥♥trt♦♥s 132 s t ♦rt ♦♥ s sr ♥ ♣r♦s st♦♥ t ♦♥ssts ♦ ♦♥ 12 ♦sr♦♥ ♥ ♦♥ ♥ ♦ ♥♠r ♦ tr♦♥s ♠s t ♠t 4s s♠♦♥t♥ 132 ♥ s 4 r②st ♦♣ t ♦♥♦ ♣r ♥t ♥ ♥② ♥ t♦r② ♥ ♥r ♥ ♥ ♣rtr♠♣s tt 132 s ♠t r ♦ t stts t t r♠ r ♦sr stts s s ♦r ♠♥ ♠♦tt♦♥ t♦ ♥stttr♦♥♣♦♥♦♥ ♦♣♥ ♥ ts ♠tr s ♣r♦t♦t②♣ ♦ ♠t♦sr strtrs

❲ tr♦r ♦♠♣t t tr♦♥♣♦♥♦♥ ♦♣♥ ♥t♦❬❪ ② r♥ r♦♥ t r♦♥ ③♦♥ ♦t♥ ♦♣♥♣r♠tr q t♦ s q♥tt② s ♥ 2❬❪ ♣♦♥♦♥ ♥st②

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P ❯

♦r♠t♦♥ ♥r② ♦ st ❬❪ ♦r♦♥ rs t T = E f

♠❱t♦♠ rst ♦♠♥ ♠♦ ♥♠ s ♥ ♦♥ ♦♠♥ r♦♥ ♦♥t♥t ♥ t tr ♦♠♥ ①♣t ♦r t polar ♠♦ ♥ t♠♥ts t ♦r♠ ♦ t ♦sr♦♥ rs♣ ♥ s ♥ ♥ rs♣ ♦t♦ rts ❱ st♥s ♦r ♥② s ♦r E f s ♦♠♣t ♥ ♦r ♦r♠t♦♥ r♦♠ α12 + ♠♦♥ s ♦ t ♦r♠t♦♥ ♥r②♦ ♣r r♦♥ ♦r ♦r♦♥ ♣ss r s♦ ♥

♦ t trs s ♦r ♦r② ①♣

r♣t [1][2] ±[5]

♠♦♥ 11p❱ [2]

Polar 4p [2][3][4] ±[6]

±[7]

11p12 ❬❪[4]

12❱ [2] [4]

12 [2] [4]

α12 [2]

❬❪ ♦r♠t♦♥ r♦♠ r♣♥ t ❱♥ r ❲s ♦rs ❬❪❬❪ ♦r♠t♦♥ r♦♠ r♣t ♥ α12 ♥ ❬❪❬❪ ❬❪❬❪ ❬❪ qr rts ♥t ♥ ♥r② r♥ ♦r E

f ❬❪ t ♥ ❬❪❬❪ ♥t♣② ♦ ♦r♠t♦♥ t ❬❪❬❪ ♥r② ♦ ♦r♠t♦♥ t ♠♥t t♠♣rtr ❬❪

s♠ s ♥ t E fB4C

♦♠♣t ♥ ♦r ♦r♠t♦♥ r♦♠ 4p + ♠♦♥ ♦r r♦♥ ♦♥♥trt♦♥ rr t♥ ♥ r♦♠ 4pα♦r♦♥ ♦r r♦♥ ♦♥♥trt♦♥ ♦r t♥

♦ t trs fB4Cp+α−B12

∆fB4Cp+diamond

11p❱ Polar 4p

11p12 12❱ 12

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P ❯ ❨

❯♥st ❬❪ ♦r♦♥ rs ♦r♠t♦♥ ♥r② E f ♠❱t♦♠r♦♠ α12 + ♠♦♥ qr rts ♥ts ♥ ♥r② r♥ ♦r f ♦♠♥ ♠♦ ♥♠ s ♥ ♦r r♦ ♥♠r ♦♠♥ r♦♥♦♥♥trt♦♥ ♦♠♥s ♥ sr♣t♦♥ ♦ t ♥ ♥ ♦ t♦sr♦♥ rs♣t② ❱ st♥s ♦r ♥② ♦♠♥ ♥ts t♦♥ t♦♠s r ♥ ♥trstt ♣♦st♦♥s ♥ ♦♠♥ ♥ts t♦sr♦♥ ♦♥t♥s ♦♥ t♦♠ t ts ♥tr

♦ ♦r t ♥ ♦sr♦♥ ♥tr ♦ s ♦r②r♦ ♥♠r stt ♥tr ♦r

102

r♦ 2 11p11

p′

❬❪ ❬❪[1]

♣♦r 2 102p12

qt♦r 11e [1]

♥ 12 s♦rr 11

p ♥

r ♥ 10p2

r♦ 12

❱❱ 11p [2]

❱ 11p [2]

❱ 11p [2]

11p [2]

r♦ 12 r♦ 12

♥♦♥ 11102 1112

r♦ ❱ 12 6

♥♦♥ 11p [2]

❱❱ 11p [2]

❱❱ 11p [2]

1212

❱ 12 [2]

❱ 12 [2]

❱ 11p [2]

❱ 11p [2]

❱❱ 12 [2]

12 [2] [1] [3]

11p [2]

❬❪ ❬❪❬❪ r♦♠ r♣t ♥ 12 ♥ ❬❪❬❪ ❬❪

Page 83: Some ab initio tudies of the physical properties of materials

P ❯

♦ stts r♣♦rt ♥ r ♥ t sr ♥t♦♥ ♥ r ♦ s t♦ ♥rst♥ tt t ♠♥t ♦ t tr♦♥♣♦♥♦♥ ♦♣♥♠♦st② ♦♠s r♦♠ ♦♣♥ t t rt♦♥s ♦ t ♦sr♦♥

♣♦♥r♥ t♦rt ♠t♦ t♦ ♦♠♣t t s♣r♦♥tt②♥♦ ♠ ♣♦ss t ♦♠♣tt♦♥ ♦ t sr♥ ♦♦♠ ♥trt♦♥ s rqr t♦ t t rt t♠♣rtr❬ ❪ ♥ ♦r t♦♥ ♥st s ♣r♠tr ♦r t ♦♦♠ r♣s♦♥ ♥ ♥ ♦r♠❬❪ ❲♥ ts ♣r♠tr s t♥ q t♦ t ♦2 ♦t♥ rt t♠♣rtr ♦ ♦♥② st② ♦ t ♦t♥ ♦r 2

♦ ♦♥ ts st♦♥ t s ♥ s♦♥ tt t rt t♠♣rtr♦r ♠t 132 s ♦♠♣r t♦ t ♦ 2 ♥ tt s♣r♦♥tt② s ♥ t♦ 12 ♥ ♦s t② ♦♠s r♦♠ ts②♥tss ♦ s♥ r②sts s sst♦♥ ①tr♣♦t♥ ♦r rstst♦ ② ♦♣ α♦r♦♥ ts s ①♣t t♦ rtr t♥ t ♦② ♦♣ ♠♦♥ s♦♥ ♦r s♦♥ r ② ♠♦r t♥ ♦♥ ♦rr♦ ♠♥t

r ♥ strtr ♦ 132 r♦♠ ❬❪ ♥r②❱ s rrr t♦ t r♠ s ♥

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P ❯ ❨

r P♦♥♦♥ ♥st② ♦ stts ♦ 132 r♦♠ ❬❪ ♦ ♥ t♦t s ♥ ♦♥trt♦♥ r♦♠ t rt♦♥s ♦ t ♦sr♦♥♦tt ♥ ♦♥trt♦♥ r♦♠ t ♣♦♥♦♥ ♠♦s ♦ t ♥

♦♥s♦♥

♥ ts ♦r r t ♥rst♥♥ ♦ t t♦♠ strtr♦ ♦r♦♥ rs ♥ r♦♠ ♥t♦ t♦♥s s ♦♠♣tt♦♥s♦ t ♥♠♦s tr♠♥t♦♥ ♦ t t♦♠ strtr ♦ 4 sr rt♦♥ ♥ s♣tr r ①♣♥ ② t ♣♦r ♠♦ ♦♥ 11p ♦sr♦♥ ♥ ♦♥ ♥ ♣r ♥t ❲ s♦♥tt t ♠♥ strtr t ♣rt r♦♠ ssttt♦♥ s♦rr ♦ tr♦♥ t♦♠ ♥ t ♣♦r st s 10

p2 ♦sr♦♥ s ts

♥ ♦sr ♥ ♦♥ ①♣r♠♥t ♦r♦r st♦♦♠tr② ♠♣s t①st♥ ♦ 12 ♦sr

♥ t♦♥ ts stst♦r② r♠♥t ♠♦r♦r s s rt ♦♥♥ ♥ t t② ♦ t♦ rt② ♣rt t s ♦ t ♦r♠t♦♥♥r② ♦ ♦r♦♥ rs t ♦♥♥trt♦♥s ♦tr t♥ ❲ s♦♥tt r② strtrs ♥ rr s ♣♦ss ♥ts ♦r ♥♠♥ strtr ♦s ♦r ♦r♦♥ rs t r♦♥ ♦♥♥trt♦♥s ♦r

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P ❯

r ♦ ♥ sr ♥t♦♥ r♦♠ ❬❪ s ♥ r tr♦♥♣♦♥♦♥ ♦♣♥ ♣r♠tr

t♥ s ♦s ♥st t ② s♣r t♦t tt ♥tr♥s strtr ts r ♥rt② ♦r t rs♣t t♦ t strtrtr ♥ ♠tstt② ♦ ♥② ♠♦ t rs♣t t♦ 4p + α♦r♦♥ ♦r 4p + ♠♦♥ ② s♥ t ♦♥ ts ♠tstt② ①♣♥ t ts ♥ t s②♥tss ♦ ♥ s♠♣s ♦ ♦r♦♥rs t r♦♥ ♦♥♥trt♦♥s ♦r t♥

st② s♦♥ tt t str♥t ♦ t tr♦♥♣♦♥♦♥ ♦♣♥♥ ♣r♦t♦t②♣ ♦sr ♠t 132 s ♦♠♣r t♦ tr♦♥♣♦♥♦♥♦♣♥ ♥ 2 r♦♠ ts ♦♥srt♦♥s ①♣t tr♦♥♣♦♥♦♥♦♣♥ ♥ ② ♦♣ α♦r♦♥ t♦ ♠♦r t♥ ♦♥ ♦rr ♦ ♠♥trtr t♥ tt ♦ ② ♦♣ s♦♥ ♦♠♥♥ s♣r♦♥tt②♥ t ♥♦♥ r♠r ♠♥ ♣r♦♣rts ♦ ♦r♦♥ rs ♥ t♦ ♠trs ♦ ♥str ♥trst

Page 86: Some ab initio tudies of the physical properties of materials

♣tr

♦♥s♦♥ ♥ ♦t♦♦

♥ t ♦♥ tr♠ t ♠t♦s ♦t s t♦ ♥rst♥ ♥ t♦ ♣rt t②s ② t tr♦♥ ①tt♦♥ ②s ♥s ♥ t t♦♠ strtr ♦ ♠tr ♥ t ♣r♦sss ② strtr ts r rt

♥ t ♣trs ♥ ♦ ts tss ♣rs♥t t t♦♦st ♦r s♣♦s t♦ t t ①tt♦♥ ♦ ♥ tr♦♥s ♥ t♦ ♥rst♥ t ♥r♣r♥ts tt s♦s ♣ ♥ t tr♦♥ ♥r② ♦ss s♣tr♥ ♥ ♦♣t s♦r♣t♦♥ s♣tr r♣♦rt rsts ♦♥ r♦s ♦①s♥ t tr t ♥♦t ♦t ♦ ♣ t♦ ♦♣ t t♦r② ♦ ♣♦t♦♠ss♦♥ ②♦♥ ts t ♠tt♦♥s ♥ ♥♦ ♥ t ♣r♦t♦t t P ♠sr♠♥t ♦♥ ♣r♦s ♦① ♥ t ♦♠♣tt♦♥ ♦t ♦rrs♣♦♥♥ ♥ strtr ❬❪ t ♥ tt rs tt♦r② ♦ tr♦♥ ♥r② ♦ss s♣tr♦s♦♣② ♥ ♦ ♦♣t s♦r♣t♦♥ s♥ ♦♣♥ t♦ t ♣♦♥t r t s r rt♥ ♠trt② ♦t ♦r s st ♥ t♦ r t s♠ ♦ ♠trt② ♥ ♦rr t♦ tt ♣♦t♦rr♥t s♣t r♥t ♥s ❬❪

♥ ② t♦ ♠ ♣r♦rss ♥ t ♦t ♦t s rst② t♦r ♣ ♥rst♥♥ ♦ ♥ ♠tr ♥ ♦ ts ts ♥ s♦♥② t♦ ♥rst♥ ts r ♦♣♥ ♥r ♥ rrt♦♥ ♥② t② ♦ s♦ ♥ t ♣tr s♠♠r③ ♠② ♥rst♥♥ ♦s♦♠ ♣②s ♣r♦♣rts ♦ ♦r♦♥ rs ♠tr ♠ s♣st ♦ r♣♦rt ts r ♣rt ② t t♦♥ t♦♦r ♥ ts ♠tr st② ♦ ♦ s ts r ♣r♦ r♥ s♦ ①♣r♠♥t ♥ ② t② rst② ♠♦② t ♠♥str♥t ♦ ts ♠tr s ♦♥♦♥ t r ♠♠♥ tr♥♥② ♥t tr t ♦ t♠♦st ♠♣♦rt♥ t♦ ♥rst♥ ♥ ♣rt ② tt♦♥ t ♥ ♦ ts ♥ ♦♣ ♥r ♥ tr♦♥ ①tt♦♥♥ s ♠tr

tr st t ♦r t s♦rttr♠ tr s t t♦r② ♦ tr♦♥♣♦♥♦♥ ♦♣♥ ♦r t tr♦♥ r①t♦♥ ♥ s♠♦♥t♦rs ♦♥srts t♦♣s s ♥ ♦♥♦♥ ♣r♦t ♦♠♥t ♥ t s

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P ❯ ❯

♥t trtr❬ ❪ ♥♦♥ ♣r♦rss s ♠ ♥ t r♠♦r♦ t ♣r♦t s♣♣♦rt ② t r♥ ♥ t♦♥♣♦r r ♦♣ tt ♥ t ♥r tr ts st ♠tr ♥♦ ♥ r♦♥③ s r② ♠♣♦rt♥t ♦♣ tt t s♦♦♥ ♦♣ ♥ t tss ♦ ♠② ♦♦rt♦r r ♥ st ♦♣♥ ♦ t tr♦♥ ①tt♦♥ t♦ ♣♦♥♦♥ ♦ ♥t t♦r♥s s t♦ ♥rst♥ t t♠ ♦ t tr♦♥ r①t♦♥ ♥①tst♣ s t♦ st② t ♦♣♥ t ♣♦♥♦♥ ♦ ♥s♥ t♦r ♦♥♥t ♥ t P tss ♦ r ♠r♦ s ♦t t♦ ts ♣♦♥t ♥①t st♣ t ♦r tr ♦r s t♦ ♥rst♥ ♦ s ♦♣♥♥ ♠♦② t t♦♠ strtr

♥② ♦ t♦ t♥ t ♠♥② ♣♦♣ t ♦♠ ♥♦r♥ ♦♣ t② ♥ t s t② t♦t t② s♦ ♥ ♣♦♦③ ts t ♥♦t t s ♣② t♥ Pr♦ss♦r ❯ ♦♥ rt ♦rs t r♥ ♦ t ♠♥sr♣t ♥ ♦tt♥ ♦r t ♦rrt♦♥s♦ t ♥s ♥ t♥ Pr♦ ❯ ♦♥ rt Pr♦ ♥ r rst♦♣ r t♦ ♣t t♦ r t ♠♥sr♣t♥ t♦ ♣rt♣t t♦ t r② ♦ ts t♥ Pr♦ r ♠rr♦♦r ♥ ♣t t♦ r t r② ♥ r rst♥ ♦① ♥ r♠ Ptt t♦ ♣t t♦ ♠♠rs ♦ t r② ♦ ts t♥ r ♠ Ptt t ♦r♠r ♦ t ♦rt♦r s ♦srrés ♦r s ♥♦r♠♥ts r♥ ts st ♥♥ ②rs

Page 88: Some ab initio tudies of the physical properties of materials

♣♣♥s ♥♥①s

Page 89: Some ab initio tudies of the physical properties of materials
Page 90: Some ab initio tudies of the physical properties of materials

♣♣♥①

sr♣t♦♥ ♦ ③r♦♥

❩r♦♥♠ ♦① s t ♦♥② tr♠♦②♥♠② st ♦♠♣♦♥ ♥ ts②st♠ ❩r ❬ ❪

❩r♦♥ ❩r2 s t♥♦♦② ♠♣♦rt♥t ♠tr t♦ ts str♥t ♥ stt② t t♠♣rtrs ♥ ts ①♥t tr ♣r♦♣rts t ♥ r stt tr ♦♥st♥t ε0 ♦ r♦♥ ❬❪ ❩r♦♥ ts s♦s r♥ ♦ ♥str ♣♣t♦♥s ♥♥ ss ♥r♠ ♥♥r♥ ♦r ①♠♣ t♦ str♥t♥ r♠s ❬❪ ♦r s♥ ♦①②♥ s♥s♦r ♥ s ❬❪ t s s♦ t♥♦♦② ♠♣♦rt♥tt②t s♣♣♦rt ♠♠ ❬❪ t s ♥♦ ♣r♦♣♦s t♦tr t ♥s t tr ♠tr ♥ ♠t♦① s♠♦♥t♦r s ❬ ❪

rtr♠♦r ③r♦♥ s ♦♥ ♦ t ♠♦st rt♦♥rsst♥t r♠srr♥t② ♥♦♥ ❬ ❪ ♥ tr♦r s ♣rtr ♠♣♦rt♥ ♥t ♥r ♥str② r t s s s ♣sst♥ ♠♠ ♦r ②r♦♥♥rss ♥ ♣rssr ts ♣r♦♣♦s ♣♣t♦♥ ♦ ♣rtr ♥trst st s ♦ ❩r2 ♠tr① ♥ ♦♣ t r♦t ♥ ♣rtr② t♥s ♥ rrt t♦ ♦r tr♥s♠tt♦♥ ♣r♦ss ♥ ♦r♠♥♦♥r♦t ♦♣♥ts ♥ t rrt ♥ ②t st ③r♦♥ ♠tr①

♦t♦♥ ♦ t strtr ♥ tr♦♥ ♣r♦♣rts ♦ ③r♦♥ s ♥t♦♥ ♦ t♦rs s s t♠♣rtr ♥ ♣rssr ♥ t ♣♦②♠♦r♣s♦ ♣r ③r♦♥ ttr♦♥ ♦r ♠♦♥♦♥ ♣ss s s tr♠①♥ t r♦s ♦①s s tr♦r t st ♦ ♥t♥s ①♣r♠♥tsts

t ♦ ♣rssrs ③r♦♥ s♣②s tr ♣ss ♠♦♥♦♥ ttr♦♥♥ r♦♥ stt ♣s ♦ ③r♦♥ ②t strtr t ♠♦♥♦♥ ♥t s st ♣ t♦ r♦♥ ❬❪ ♠♦♥♦♥♥t ♦♥t♥s ♦r ❩r2 ♥ts ♠❩r2 t ♠♦♥♦♥ ③r♦♥ ♠❩r2 ♥r♦s rst♦rr ♠rt♥st tr♥st♦♥ t♦tr♥s♦r♠ ♥t♦ ttr♦♥ ♣s ❬❪ t❩r2 ② ♥rs♥t t♠♣rtr t♦ s♣ tr♥st♦♥ ts ♣ ♥ t❩r2 ♥

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PP❳ P ❩

t ♦rt ♣s c❩r2 s ♦t♥ ❬ ❪ s t♥ st ♣ t♦ t ♠t♥ t♠♣rtr ♦ ❬❪

♦♦r♥t♦♥ ♥♠r ♦ t ③r♦♥♠ t♦♠ s Z ♥ t ♥ttr♦♥ strtrs ♥ Z ♥ t ♠♦♥♦♥ ♣s

s♦ st ♥ ②♣♦tt rt strtr t Z s st st strtr ♦r 2 s s♦tr♦♥ t ③r♦♥ st rt ♣s s t♦♦ t♦ ♥stt ts ♦ t r②st ♥ ③r♦♥♥ ttr ♥rst♥ t ♣r♦♣rts ♦ t ♦♠♣① ♠♦♥♦♥ ♣s ♦③r♦♥

♥ ♠② t♦♥s ♦♥ tt t ♥r② ♦ t ♣ss ♦♦s t ①♣r♠♥t ♣s r♠ t ♠♦♥♦♥ ♣s s t ♠♦st st ♣st♥ t ttr♦♥ ♦♥ ♥ ♥② t ♦♥ ❬❪ ♦♥tss ❩♥③♦tt♦ s r♥t② r♥ ♠② tt♥t♦♥ ♦♥ t t tt t ♣rssr♦rt♦r♦♠ ♣s s♦s ♥ ♥r② r t♥ t ♥r② ♦ t ♠♦♥♦♥ ♣s ♥ ♦r t♥ t ♥r② ♦ t ttr♦♥ ♦♥ ❬❪ ♥♦ t♥ ss♣t tt t ♦rt♦r♦♠ ♣s ♦ ♦r s ♥ ♥tr♠t ♣s ♥ t ♣s r♠ ♦ ③r♦♥ ♥ t t♠♣rtr s♥rs ts ②♥ t ♦rr ♠♦♥♦♥ ♦rt♦r♦♠ ttr♦♥ ♥ rst ♥st ♦ t ①♣r♠♥t ♦rr ♠♦♥♦♥ t♥ ttr♦♥♥ ♥② ♣s

② ♣rs♦♥ s tt s ♥ r♣r♦♥ rt s ♦ tt♦t ♥r② s s♦♦♥ s ♦♥ ♦♠♣rs rst ♣ss r♥t♥♠rs ♦ tr♦♥s ♦r ♥♠rs ♦ t♦♠s ♦ r ♥♦♥tr ♣r♦♠s♥ ♦♠♣r♥ ♣s ♦ ❩r 2 ♥ ♣r♦② ❩r2

♥ t tr t ♥ssr② t♦ r② tr t s s♦♥ r♣r♦♥ t ♣s r♠ ♦ ③r♦♥ ♦r tr t s ♥♦t strt♦rr t♦ ss t ♦r ♥ rs♥ t♠♣rtr ♦ ts ♦♠♣①s②st♠s r♦♠ t ♥rts ♦

Page 92: Some ab initio tudies of the physical properties of materials

PP❳ P ❩

r ♣r♠t ♥t ♦ ♦r t♦♠ strtrs ♦ ③r♦♥ ❩r2 ttr♦♥ ❩r2 ♠♦♥♦♥ ❩r2 ③r♦♥ ♥ t②♣♦tt rt ♣s r s♣r ③r♦♥♠ t♦♠ ♠ s♣r ♦①②♥ t♦♠ ♦r t ♠♦♥♦♥ ♣s t t♦ r♥t ♦①②♥ sts rs♦♥ ♥ r♥t ss r♦♠ ❬❪

Page 93: Some ab initio tudies of the physical properties of materials
Page 94: Some ab initio tudies of the physical properties of materials

♣♣♥①

② r r♠s ♦♥ r

♥ ts ♥♥① sr ♦♥ ② t♦ r r♠s ♦♥ r

♦♠♥ t♦ st♦♥ ♦♥ ss ♥♦ t♦ ♦♠♣t t ♣r♦t② ♦r ♦r s②st♠ t♦ ♠ tr♥st♦♥ r♦♠ t ♥♣rtr ♥t stt|ψ

(0)nk > t♦ ♥♦tr ♥ stt |ψf > ♥r t ♥♥ ♦ ♣rtrt♦♥

♦♦♥ ❬❪ s♣♣♦s t ttr t♦ t♠ ♣r♦ ♥ t② st t t♠ t = −∞ s ♥ st♦♥

t s s♣♣♦s tt t ♥r② ♦ t ♣rtrt♦♥ s ~ω ♥ tt t♥t t♠ t s②st♠ s ♥ t stt t ♥r② ε(0)

nk a(0)nk = 1 ♥

a(0)pk′ = 0 ♦r p 6= n ♦r k′ 6= k

①♠♥t♦♥ ♦ t ♥♦♠♥t♦rs ♥ q s♦s tt t s ♦t ♥ ♥r② ♦r ts ♥♦♠♥t♦rs r r r t rs♦♥♥t♦♥s ♦r ♥st♥ ♥ ε(0)

f = ε(0)nk + ~ω

qrtr t♥ rs

a(1)f (t) =

−i

~

∫ t

t0=−∞

e−i(ε(0)nk

−ε(0)f

) τ

~ < ψ(0)f |F q †|ψ

(0)nk > e−iωteαtdτ ,

♦s s♦t♦♥ s

a(1)f (t) =

e−i(ε(0)nk

−ε(0)f

+~ω+i~α) t~

ε(0)nk − ε

(0)f + ~ω + i~α

< ψ(0)f |F q †|ψ

(0)nk > .

tr♥st♦♥ ♣r♦t② r♦♠ t ♥t stt ψ(0)nk t♦ stts ψ(0)

f ♦s♥r② s t♥ ♥ ♥r② r♥ dνf rs

dwf ;nk = |a(1)f (t)|2dνf ,

r

|a(1)f (t)|2 =

| < ψ(0)f |F q †|ψ

(0)nk > |2e2αt

(ε(0)nk − ε

(0)f + ~ω)2 + (~α)2

.

Page 95: Some ab initio tudies of the physical properties of materials

PP❳ ❨ ❯ ❯

♥ s

d |a(1)f (t)|2

dtdνf =

2α| < ψ(0)f |F q †|ψ

(0)nk > |2e2αt

(ε(0)nk − ε

(0)f + ~ω)2 + (~α)2

.

❯s♥ t t tt

limx→0x

π(ǫ2 + x2)= δ(ǫ),

♦♥ ♥s tt

limα→0d |a

(1)f (t)|2

dt=

~| < ψ

(0)f |F q †|ψ

(0)nk > |2δ(ε

(0)nk − ε

(0)f + ~ω)

♥② t ♣r♦t② ♣r t♠ ♥t ♥ ♣r stt ♠♦♥ts t♦ r♠s♦♥ r

dwf ;nk

dνf

=2π

~| < ψ

(0)f |F q †|ψ

(0)nk > |2δ(ε

(0)nk − ε

(0)f + ~ω)

Page 96: Some ab initio tudies of the physical properties of materials

♣♣♥①

rr♠ t ❱st r

Page 97: Some ab initio tudies of the physical properties of materials

PP❳ ❯❯❯ ❱ ❱

♦♠ t ❱P♦st P②s♥♥ rr

①♣rt s♥♦r ♥s♥ s♦t♥♥ ♣ré t ♠ ♥tst♣♦②t♥q

♦♥♥és ♣r♦ss♦♥♥s tt tt♦♥ ♥ss♥ r♥

♦ s ♦s rrés t♦♥té r♥çs♦ P♦②t♥q

♦♠♥ ①♣rtsP②sq té♦rq t ♥♠érq ♣♦r tèr ♦♥♥sét ♥t♦ s ♣r♦♣rétés ♣②sqs s ♠tér①ét♦s sés sr é♦r ♦♥t♦♥♥ ♥sté tt♣♥♦♣r③♦r♥♦❴♣r③s♠str②rts♦♥trt♠

t à ts à ♦r♣s ♣♦r

• s♣tr♦s♦♣ étr♦♥q t rt♦♥♥• s ♠é♥s♠s ①tt♦♥ t r①t♦♥ étr♦♥q♣rtèr♠♥t és①tt♦♥ ♣r ♦♣ étr♦♥ ♣♦♥♦♥

♣♣t♦♥s ① ♠tér① ♥térêt ♣♦r s♣é♠♥t

• s r♠♠s ♣s tt♥ t ③r♦♥♠• s♣tr♦s♦♣ s ♦①②s ♠ét① ♥♦s t tr♥st♦♥ 2❩r2 2 ♣r ♣rt é♥r étr♦♥q ♣♦t♦é♠ss♦♥s♦r♣t♦♥ ♦♣tq

• s s♦s rs ♥ ♦r• s ♥♥♦strtrs s♠♦♥trs

♣ést s rrs ♦r t s ♠tér① rs ♥ ♦r

❱ ♦r♠t♦♥ t tt♦♥ à rr s rrs ❯♥rsté P t r ès ♦t♦rt ❯♥rsté Prr t r r Prs ❱

♥ s ♠tér① ♠♥t♦♥ étt♦♥s r② à ♥♥♠té ♣ô♠ éts ♣♣r♦♦♥s

❯♥rsté té s♥tq ❱♥ sq r♥P②sq étt s♦ ♠♥t♦♥ ♥

♣ô♠ ♥é♥r ♥sttt ♣érr tr♦♥q ♦r r♥ ♣t♦♥ ♣②sq étt s♦

Page 98: Some ab initio tudies of the physical properties of materials

PP❳ ❯❯❯ ❱ ❱

❱ Pr♦rs ♣r♦ss♦♥♥ ♦♥ éq♥t rtr rr ①♣rt s♥♦r rr à rr à rt♦♥ s ♣♣t♦♥s trs

♥tr ts ♠❱♥t♦♥ ♣s s r②èrs âts ♥t♦ éqt♦♥ étt ♠tér① ②♥♠q♠♦ér r Pr♥♦ strtr étr♦♥q rt♦♥s rés

❯♥rsté r♥ ❱é ♠♣s sr r♥r① rés ♣②sq ♥♠érq rs♥

❱ Prs♣ts t ♦♦rt♦♥s

s tr♦s r♥èrs ♥♥és é♦♣♣é ♥ ♠ét♦ ♥t♦ ♣♦rr t♠♣s ♥ étr♦♥ ①té ♥s ♥ ♦♥t♦♥q st ♠té ♣r ♥trt♦♥ s ♣♦♥♦♥s ♦rt ♦♥r ♦♥tr rts ♦♥t été érts ♥ ♦♦rt♦♥ st♣♦st♦ t ❱ ②tr ♣r♦ssr à ❯♥rsté Pé♦q ♦♠sss str

r q♥ t s s②stè♠s st rét à é ♥♥♦♠étrq ♦♣ étr♦♥♣♦♥♦♥ ♥t très ♠♣♦rt♥t ♣♦r tr♥s♣♦rttr♠q s♦t ét♥r ♠ét♦ ① ♣♦♥♦♥s r♥♦♥r ♦♥ ♠♣♦rt♥ts ♣♦r tr♥s♣♦rt tr♠q ♥ ♦♦rt♦♥ ♥♦s ♦ès r t ③③r ♥sttt ♥ér♦ t P②sq s ① ♦♥♥sés ❯♥rsté Prs ❱ P t r tt♦ ♥♦ ♥s ♣r♦tP

tr sr s ♠tér① à s ♦r ♠♥é à ♥ ♦♦rt♦♥ s ①♣ér♠♥ttrs t s té♦r♥s ❯♥rsté s♣♦♥ ♣♦r r♥r s s♦s s♣r♦♥tr s r♦r ♦t♦r♥t ♥♣♣♦♥ r ♥q ♠♦s ♥ é♠rr tès r ♠r♦ st ♣ré à r♥tré s♦srésr ♥♥♠♥t

♥♥ ss ♥tr♥t♦♥♠♥t r♦♥♥ ♦♠♠ ♥ s♣ést srr ♦r ♥s r é♥é ♥ ♦♥trt ♣♦r♦♠♣r♥r t♥ ♠é♥q s ♠tér① ❯♥ r♥ ♣r♦rès st ♥♦rs sr rô s ♥s ♥s t♥ ♠é♥q ♠tér ♦♥tét st t♠♥t ♠♥é tr♥♥②

❱ ♦♦r♥t♦♥ ♣r♦ts s♥tqs

♥s ♣r♦t P ♦♦r♥t♦♥ tr éq♣

♥s rés ①♥ r♦♣é♥ ❯ Prt♣t♦♥ à értr s r♣♣♦rts t ① rs ♣r♦t à r①stt♣♠t②♦r♥♥♦q♥t

Page 99: Some ab initio tudies of the physical properties of materials

PP❳ ❯❯❯ ❱ ❱

t ♦♦r♥t♦♥ ♣r♦ts s♥tqs

♥s rés ①♥ r♦♣é♥ ❯

Prt♣t♦♥ à ♦♦r♥t♦♥ ♥ s éq♣s ♥tért♦♥ s♥tqs♦t ♠♥s♦♥ strtr q♥t♠ ♦t ♥ ♦♥qr ts ♥r♦♥♠♥t

♦♦r♥t♦♥ éq♣ ♥tért♦♥ ❯ ❱♦♥ rt t st sr s♦t② sss♥ ♦♠♣r♥s ♣r♦r♠ s ♥ ♦r♠t ♥ ♠♣♠♥t t♦ ts♦t sss ♥♥ ♥r ♥ t qst♦♥s s♥t sss ♥ ts ♠sr♠♥t♠② sss ♦♥trt qst♦♥s ♠♥t♦r♥ ♥ ♠♥♠♥t tr♥♥ ♥t♥ t♦ ♣ ♥♣rtr t rr ♦♣♠♥t ♦ ②♦♥ rsrrs

❱ s♣♦♥stés s♥tqs

♦♥trts

♦♥trt P ♥t♦ ♦♣ r ♥ r♠r♥s♣rt ♥ ♥♦strtrs ♥♥♠♥t ♣♦st♦ ♠♦s tr♥♥②

♦♥trt sr ét té♦rq s rrs ♦r♥♥♠♥t ♣♦st♦ tr♥♥② t st

♦♥trt r♦♣é♥ rés ①♥ ♥♦q♥t♥♥♠♥t ♥ ♣♦st♦ tr♦s ♥s st

P♦sts ♦ P♦②t♥q ♣♦r s sts ❱ ②tr ♣♥♥t ♠♦s ré♣rts sr

♦♥trt ♥s r P ♦♥trt Pr♦r♠♠ r♦♥ts ♦ést♦♥ rrt♦♥ sr s ①tt♦♥sétr♦♥qs ♥s ③r♦♥ ❩r♥♥♠♥t ♥ ♣♦st♦ ♠♦s P r♥ s

q ♥♥é ♣r♦t ♦♥s s♥tq ♥trsé ♣r♦t ♣trtr étr♦♥q t ♣r♦♣rétés rt♦♥♥s s ♠tér① s ♥t♦

♣s ♣r♦t r♥ q♣♠♥t t♦♥ ♥t♥s trtr étr♦♥q t ♣r♦♣rétés rt♦♥♥s s ♠tér① s ♥t♦

rt♦♥ tès

t té♦rq ♦♣ étr♦♥♣♦♥♦♥ ♥s s ♠tér① és①tt♦♥étr♦♥q s♣r♦♥tté ♠r♦ é♠rr ♣ré à r♥tré

Page 100: Some ab initio tudies of the physical properties of materials

PP❳ ❯❯❯ ❱ ❱

t rs♣♦♥stés s♥tqs ♦rt♦♥ tèss r ♦t♦r♥t ♥♦s♥ ♥ ♥♦t♥♦♦② ♥tr ♥sttt ♦ ♥t ♥ ♥str sr s ❯♥rst② ♣♥♥♦②é ♣♦r étr s♣r♦♥tté ♦r t ♦r ♦♣é♦ ♥r t ♥t

t té♦rq s ♣ss tt♥ ❱ r♥té éqt♦ P♦②t♥q tt♣♠♣r♠r♣♦②t♥qrsssr♥t♣

①♥ ♥ ♦rrt♦♥ ♥ t tr♦♥ trtr ♦ ♦s r♦♠ ♦♥t♦ ♣r♦s ♦① ❲ ♣♣r♦①♠t♦♥ ♥ ②♦♥ r♥ ♦ P♦②t♥q

♠♠♣r ♥ ♥t♦ t♦♥s ♦ ♦♣t ♣r♦♣rts ♥ s♠♦♥t♦rs♣rtts ♦tt ❯♥rstà P t

Pt♦♥s ♣♣rs ♥s s ♦r♥① à rrs ♦♥t rts ♥s P②s ttrs t rts ♥s P②s rts ♣s ♠♦♥ à rré à

rts ♥é♥ts ♣r♦r♠♠s ♥♦r♠tqs q é♦♣♣ s♦♥t s♦s ♥ ❯

♥tt♦♥s ②♥♦t tr tt t♥ è♠ ♥tr♥t♦♥ ②♠♣♦s♠♦♥ ♥trt♦♥ ♦♠♣♦♥s à ♥ ♥

P♣r ♥té à t ♥tr♥t♦♥ ②♠♣♦s♠ ♦♥ ♦r♦♥ ♦rs♥ t trs à ts ♣♦♥ ♣t♠r

♣r♦t à ♦♠♠ss♦♥ r♦♣é♥♥ sr è♠ ♥♥é rés ①♥ ♥♦q♥t ss♦s ♣t♠r ①♣♦sésééés à st t str♦ r♥

♥♦♥tr ♥♥ r♦♣♠♥t r r♦ t ♥♦tr♠q②♦♥ ♥ ♦r ♥té sr ①tt♦♥ t r①t♦♥étr♦♥q éts ♥t♦

♦♥rès ♥♥ r♦♣♠♥t r♥çs ♣♦r s ér♠qs♥ r♥ rs ♦r ♥té sr①tt♦♥ t r①t♦♥ étr♦♥q éts ♥t♦

r r r♥♥ ♦rs ♦r ♠t♦♥st♦r ♠t♥ ♠ttr t t ♥♥♦s s♥ ♥st②♥t♦♥ t♦r② ♣s♦♣♦t♥ts ♥ ♣♥ s ②♦♥ r♥ ♦♠r ♥tt♦♥ à ♦♥♥r ① ♦rs

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PP❳ ❯❯❯ ❱ ❱

t ♥tt♦♥s

♣r♦t à ♦♠♠ss♦♥ r♦♣é♥♥ è♠ ♥♥é rés①♥ ♥♦q♥t r①s ♣t♠r ♥ ①♣♦sé s♥tq s②♥tès sr q♣ ♥tért♦♥ q ♦♦♦r♦♥♥é

❲♦rs♦♣ ♥s ♥ t t♦♠s ♥rst♥♥ ♦ ♥♥♦strtrs r ♦r ♥té sr tr♦♥ ①tt♦♥s ♥t♦ t♦♥s ♦ tr♦♥ s♣tr

♣r♦t à ♦♠♠ss♦♥ r♦♣é♥♥ sr èr ♥♥é rés ①♥ ♥♦q♥t r①s ♦ût ♥ ①♣♦sé s♥tq s②♥tès sr éq♣ ♥tért♦♥ q ♦♦♦r♦♥♥ t ♥ ①♣♦sé sr ♣♦tq s♦ s♥ rés ①♥

♥tr♥t♦♥ ♦♥r♥ ♦ ♦♠♣tt♦♥ t♦s ♥ ♥s♥ ♥♥r♥ ❱♦♠♥♦r rè ♦♠r ②♠♣♦s♠ sr ♠ts ♠♦♥ ♦ rrt♦♥ ts ♥ s♦s ♥ ss♦t♦t♦qr♠ ♣r♦sss ①♣♦sé ♥té sr s♣tr♦s♦♣ ♣rté♥r étr♦♥q

♥♦♥tr ♥♥ és ♦r♠t♦♥ r♦♣é♥ sr r♥♥ t♦r Prs t♦r ①♣♦sé ♥té sr s♣tr♦s♦♣ ♣rté♥r étr♦♥q

P ❲♦rs♦♣ ♦t♦♥s ♦♦♥ r♥t ♣r♦sss t srs♥ st♥ s♣♥ ♣t♠r ①♣♦sé ♥té sr ♥s♦tr♦♣② ♦ t♠r♦s♦♣ tt♦♥s ♦ t ♣♦r③t♦♥ ♦♥♥♠♥t ts ♥ ttr ♥t♦♥ ♦ r②sts

PPs ♦rs♦♣ ♥t♦ ♠♥②♦② t♦r② ♦r ♦rrt tr♦♥ s②st♠srst t ♦ût ①♣♦sé ♥té sr ♥s♦tr♦♣② ♦ t ♠r♦s♦♣tt♦♥s ♦ t ♣♦r③t♦♥ ♦♥♥♠♥t ts ♥ t tr ♥t♦♥ ♦ r②st

Pr♦t ♦s♦ t♦r ①♣♦sé ♥té sr ♥t♦ ♠t♦s t♦ tt tr♦♥ strtr ♥ t rt♦♥ ♣r♦♣rts ♦ s♦s

é♠♥r ♥té à ♦ ♥tr Prs ât♥②r② ♥ sr sét♦s ♥t♦ ♣♦r s ♣r♦♣rétés s♣tr♦s♦♣qs s ♠tér①

♦♥rès é♥ér ♦été r♥çs P②sq trs♦r t ♦♦q tér① ① ♦♥t♦♥s ①tr♠ês ①♣♦sé ♥té sr t ♥t♦s ♠tér① s♦s t ♣rss♦♥ tr♥st♦♥s ♣ss ét♥ s♣trs♦r♣t♦♥ ♥rr♦ ♦r ♣

❲♦rs♦♣ ♥s ♥ rst♣r♥♣s ♦♠♣tt♦♥ ♦♥♥s ♠ttr ♣②ssr♦rs r s♣♥ ♥r ①♣♦sé ♥té sr t♦♠ strtr♥ rt♦♥ ♣r♦♣rts ♦ ♦sr 4 ♦r♦♥ r

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PP❳ ❯❯❯ ❱ ❱

❳ ①♣rts s♥tq♣♣♦rtr s ♦r♥① ♣r♦ss♦♥♥s

tr trs ♣♣ P②ss ttrs P②s ttrsP②s r♦♣♥ P②s ttrs r♦♣♥ P②s ♦r♥ ♦r♥ ♦ P②s ♠str② ♥tr♥t♦♥ ♦r♥ ♦ ♥♦t♥♦♦②♦♠♣tt♦♥ trs ♥ sr P♦s♦♣ ♠③♥♠ P②ss ttrs P②s ♣rtts ♥ r♦strtrsP②s tts ♦ ♣ sr Prssr sr ②♦rr♥s♦r♥ ♦ ♣②ss ♦♥r♥ srs

♣♣♦rtr s tèss ♦t♦rt

❩♠③♠ ♥♦♥♥tt♦♥ t tèr ❯trr♦rt♦r tér① t Pé♥♦♠è♥s ♥tqs ❯♥rsté Prs

♠♦r♦ tr♦♥♦ ①tt♦♥s ♥ ♦♣t s♣tr♦ rr s s♦s r♥t② ♦ ♥

r②s tès t ♠str

①♠♥tr ♥s r② tès ss♦r t rt♦♥♥ ss s♠♦♥trs ❱ t ❱ ❯♥rsté P ❱r♥ t③

①♠♥tr ♥s r② tès r② trtr ♦ t♦r s♠♣rtés ♥s s ♠♠s été ♣r s♣tr♦s♦♣s t s ♥t♦❯♥rsté Prs ❱

♥ ♠♠r r② ♣résé ♣r Pr♦ è ♣t ♠str tér① ♣♦r s trtrs t ♥r sr étté sr ♥sàs s♦♥ ♥trt♦♥ ♦♥ r♥② ♥ ♣♣r♦ té♦rq t sr♦♥trt♦♥ à t s ♣r♦♣rétés tr♥s♣♦rt t♦♠q ♥s s ♦①②sr♥♠ ♣r ♠♦ést♦♥ ♥t♦

♦♦r♥st♦♥ ♦♥ér♥s

t r♠♦tr tr♥s♣♦rt ♣r♦rss ♥ rst ♣r♥♣s ♥♦tr ♣♣r♦s ♥ t ♥tr♣② t ①♣r♠♥t s♥♥ ss

♦ût ♦r♥és tèr ♦♥♥sé trs♦r♥♦♦q ét♦s ♥♠érqs ♣♦r tr♥s♣♦rt étr♦♥q t tr♠q ♥ss s♠♦♥trs

q ♥♥é ♦♥ér♥ ♥tr♥t♦♥ ❯ ♥ ♣rtr♥ ②rs ♦ t ❲ ♣♣r♦①♠t♦♥ ♦r t tr♦♥ s♥r②tt♣③❲

Pr♦rss ♥ ♥t♦ ♦♠♣tt♦♥ ♠t♦s ♦r ♦♥♥s ♠ttr♥r sr❨tt r♥

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PP❳ ❯❯❯ ❱ ❱

t♦♥ ♣r♦ts

♣♣♦rts ❯ r♠② sr sr s ♠tér① rs ♥ ♦r

♣s ét♦♥ s ♦ssr ♠♥s t♠♣s sr s ♦r♥trs t♦ ♥s♥♠♥t s♣érr ♣♦r ♦♠té té♠tq P②sq ♠ t Pr♦♣rétés stér①

❳ ♥s♥♠♥t t ♦r♠t♦♥ ♣r♦ss♦♥♥

r♦♣♥ ❯♥♦♥ r r r♥♥ ♦rs ♦r ♠t♦♥st♦r ♠t♥ ♠ttr t t ♥♥♦s s♥ ♥st② ♥t♦♥ t♦r②♣s♦♣♦t♥ts ♥ ♣♥ s ②♦♥ r♥ ♦♠r ♥tt♦♥ à ♦♥♥r ① ♦rs qtr rs

♥ ❯♥rsté r♥ ❱ér① rés ♣②sq ♥♠érq rs♥

trs rçs ♦rt♦r s ♦s rrés

s♠♦♥ é t té♦rq rr s♠st ♠str ❯♥rsté P t r ♦ést♦♥ ttstq t♦rt♠q s s②stè♠s ♦rs éqr rst ♦♥r♠♥t st t ❱st

❳r ❩③rtt t t s étts s♠♦r ♥s strtr ♥s t ét s♦s ♣rss♦♥ st ♠str ♦ ♥tr tér①t strtrs ♣♦r ♥r érrt ♦♥r♠♥t st t ❱st

♣♥ t t ♠♦ést♦♥ ♠ét ③r♦♥♠ t ♦①② ❩r2st ♠îtrs ❯♥rsté Prr t r r ♥ ♦♥r♠♥t s t ❱st

♦sé t té♦rq ♦①② tt♥ 23st îtrs ♣②sq ♦♥♠♥t ❯♥ Prs ♥

❱r♥ éqt é♦♣♣♠♥ts té♦rqs ♣♦r ♦①② tt♥ 2st ♥s s tér① Prs t st ♥é♥r ♦ ♥tr Prs ♣t♠r

é♠ r t té♦rq ♦①② tt♥ 23♥ ♠stèr P②sq ♦♥♠♥t rs② r ♠ t

♥ r♥ t ♥t♦ ♠t ssq t♥sr étrq♥s s étér♦strtrs ss st ♥s s tér① Prs t st ♥é♥r ♦ ♥tr Prs ♣t♠r

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PP❳ ❯❯❯ ❱ ❱

❳ rs

♥s♥s ♠♥ t♥ ♣♣r♥tss ♣♦♥s ♣s ♣t

♠r ♠r♥ P②s ♦t② ♣s ♦été r♥çs P②sq ♣s é ♦♥s ♦rt♦r s ♦s rrés ss♦t♦♥ ♠♠s t ♥s ♦♥é ♣r ♥ r♠♥♥♣r♠èr ♣r♦ssr ♣②sq à ♦ P♦②t♥q ♣♦r ttr♦♥tr s ♣réés sr s rrèrs s♥tqs é♠♥♥

♦♠♣ét♥s t♥qsPr♦r♠♠t♦♥ t sr s ♥trs s ♥t♦♥① t ts♥t s rss♦rs t♦rs t♦ ♣rèsstr ♣r♦ssrs ♣tr♦♥ ♣♦st tr s♦s ❯❳

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Page 106: Some ab initio tudies of the physical properties of materials

♣♣♥①

st ♣t♦♥s ❱str

♥tr r♦ts st ♥qé ♥♦♠r tt♦♥s ♣♣r ♥s ♦ s♥ r ♥ ♣♣rs s♦♥t tés ♦s t ♣s ♣♣rs s♦♥t ♦s t ♣s♥ ♦r rt ♥♦♠r tt♦♥ ♦ ♥ étt

P♣rs rést♥t ♠s tr①

rr ♦rt♦r s ♦s

rrés

tr♥♥② ❱st ♥ st ♦r♦♥ r t ♣rssr ♥ ♣ré♣rt♦♥

❱st t ♥t♦ s ♣r♦♣rétés ♣②sqs s♠tér① ♦♠♥t tt♦♥ à rr s rrs

❱st st ♥ tr♥♥② ♦r♦♥ rs r♦♠ rst♣r♥♣s ♦r♥ ♦ P②ss ♦♥r♥ ♣r♦♥s rt r r♣♣♦rtrs ♦s ♣rss

st ❱st ♥ tr♥♥② r♠ ♥rt♦♥ ♣r♦♣rts ♦ ♦r♦♥ r t r♦♥ ♦♥♥trt♦♥♥ ♥t♦ st② ♥ ♣ré♣rt♦♥

❬❪ st ❱st ♥ ❱ ②tr ♥t♦ st② ♦tr♦♥♣♦♥♦♥ ♦♣♥ ♥ ①t♦♥ ♥t ♥ s ♥r♣rssr ♥ P ♦r♥ ♦ ♠♥s♥ ❯ tt♣①♦♦r♠♥

❬❪ st ❱st ♥ ❱ ②tr ♥t♦ ♠t♦ ♦r ttr♦♥♣♦♥♦♥ sttr♥ t♠s ♥ s♠♦♥t♦rs ♣♣t♦♥ t♦

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PP❳ P❯ ❱

s ♥ P P②s ttrs t② t ♠r♥ P②s ♦t② ♦r t ♥r② ss ♦❱rt ♦r♥ ♦ ❯trst ♥ tt♣trst♦r❯ tt♣♥♣s♦r♦P②stt

❬❪ ❱r♥ r♥té t ❱st ♥ r ②♦♥ t ♦ t♦③t♦♥ ♦ t s♠♦r ♥st② ♦♥ t ♣②s ♣r♦♣rts ♦tr♥st♦♥ ♠ts P②s ♦♥ ttr ❯ tt♣①♦♦r

st ❱ ②tr ♥ ❱st ♥ Pr♦♥s ♦ ♥t♦♥r♥ ♠ rs♥ ♥ ❱ r♦♣ t ♦♠♣♦♥ss t♦r ♦♠s ss ♦♠ ❱ ♣s ♦♥♥

❬❪ ♥ r♥ t ❱st ♥♥ ③qr♦ r♦tt ♥ rrtt ①♥ ♥ ♦rrt♦♥ ts ♥tr♦♥ ①tt♦♥ ♦ 2 P②s tt ❯ tt♣♥♣s♦r♦P②stt

❬❪ st ❱ ②tr ♥ ❱st ♥tr② sttr♥ ♥s ♥t♦ t♦♥ ♦ t t ♣r♠trs ♦r ♦♥tr♦ s♠t♦♥s ♣♣ P②ss ❯ tt♣①♦♦rs

❬❪ st ❱ ②tr ♥ ❱st ♥t♦ st② ♦ Γ − X

♥tr② sttr♥ ♥ s ♥r ♣rssr P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ ♥ r♥ t ❱st ♥ ♥♥ t ♦s♦♥sst♥② ♦♥ qs♣rts ♥ s♦s P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ s ♥ r♥ ❱r♥ r♥té t ❱st ♥ ♥♥ tr♦♥ ①tt♦♥s ♥t♦ t♦♥s ♦tr♦♥ s♣tr ♥ ♣♣t♦♥ t♦ ③r♦♥ ❩r2 tt♥ 2 ♥♣r♦s ♦① 2 ♦♠♣ t ❯ tt♣①♦♦r♦♠♠ts

❬❪ ❱ ②tr ♥ ❱st r♥♥s qt♦♥ ♦ stt ♦r ttr♦♥ r♦♥ stt ♥r② ♦♠♣ t ❯ tt♣①♦♦r♦♠♠ts

❬❪ ♦tt r♥ r♥♦♣♦♦s s ♦tt❱ ♥♦ ❱st ♦ ♥ ♥♥ r♦♠♠♦s t♦ s♦s t r♦ ♦ ♦♥r♥ ♥trt♦♥s ♥t ♥t♠ ❯ tt♣①♦♦rq

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PP❳ P❯ ❱

❬❪ s t ❱st P♣♣ r♥ r②♥t ♥ ♥♥ tr♦♥ strtr ♥ tr♦♥♥r②♦ss s♣tr♦s♦♣② ♦ ❩r2 ③r♦♥ P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ ♦tt ❱st ♥♥ ❱ ♥♦ ♥ ♥r♥ ♥t♦ ♥ s♠♠♣r tr rs♣♦♥s ♦ s♣rtts P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ tt♦ ♥r t ❱st ♥ r♥s♦ r♣r♦♥tt② r♦♠ ♦♣♥ ♦r♦♥ ♦sr P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ ♥ ♦tt r♥s♦ ♦tt t ❱st ❱r♦ ♥♦ ♥♥ ♥srst♥ ❲ssr ♥ ♦ ♦♥♥♥ ♦♦♦ ♦ ♥ ❲ ♦② ♦♥r♥ ♦♥trt♦♥t♦ t ①♥♦rrt♦♥ r♥ ♦ t♠♣♥♥t ♥st②♥t♦♥ t♦r② P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ r♥♦♣♦♦s ♥♥ ♦ ♥ ❱st ♣t♥ ♦ss s♣tr ♦ r♦♥ ♥♥♦ts ♣♦r③t♦♥ ts ♥♥trt ♥trt♦♥s P②s tt ❯ tt♣♥♣s♦r♦P②stt

❬❪ ♦tt ❱st ♥♥ ❱ ♥♦ ♥ ♥r♥ ♥t♦ t♦♥ ♦ t tr t♥s♦r ♦ sss♣rtts P②s tt ❯ tt♣♥♣s♦r♦Pstt

❬❪ ❱st ♥♥ ❱ ♥♦ P tts♥r ♥ ♦r② ♦ ts ♥ t ♥s♦tr♦♣② ♦ t tr♦♥♥r② ♦ss s♣tr♠ ♦ tt♥♠ ♦① 2 P②s tt ❯ tt♣♥♣s♦r♦P②stt

❬❪ r ❱st ♥ Pr t♦♠ strtr ♦♦sr 4 ♦r♦♥ r r♦♠ rst♣r♥♣s ♥②ss ♦ s♣tr P②s tt ❯ tt♣♥♣s♦r♦P②stt

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PP❳ P❯ ❱

P♣rs rést♥t ♠s tr①

rr

❬❪ ❱st ♥ r♦♥ ts ♦ s♦t♦♣ s♦rr ♦♥ t ♠♥s♣tr♠ ♦ r②sts t♦r② ♥ ♥t♦ t♦♥ ♦♥ ♠♦♥♥ r♠♥♠ P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ ❱st ♥ r♦♥ ts ♦ s♦t♦♣ s♦rr ♦♥ t ♠♥s♣tr♠ ♦ r②sts t♦r② ♥ ♥t♦ t♦♥ ♦♥ ♠♦♥♥ r♠♥♠ ♦♠♣ t ❯ tt♣①♦♦r

❬❪ ③③r ❱st ss♦♥ r♦♥ ♥ ♥r ♦rs♦ trtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr 4♦r♦♥ r P②s tt ❬❪ ③③r ❱st ss♦♥ r♦♥ ♥ ♥r ♦rs♦ rrt♠ strtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr4 ♦r♦♥ r P②s tt ❯ tt♣♥♣s♦r♦P②stt❯ tt♣♥♣s♦r♦P②stt

❬❪ ❱st ss♦♥ r♦♥ ♥ ♦rs♦ t♦♠strtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr α♦r♦♥ ♥ 4♦r♦♥ r ♦♠♣ t ❯ tt♣①♦♦r

❬❪ t ❱st Pr♦♣rétés rt♦♥♥s ♦r α t rr ♦r 4 ès ♦t♦rt ❯♥rsté Prs ❱ r♥ tr♣♣♦rt ❯ tt♣trs♦rtsrtr

❬❪ ❱st r♦♥ ❩ér ss♦♥ P♦♥ r♠st ♥ r♥ tt ②♥♠s ♦ ♦srα♦r♦♥ ♥r ♣rssr P②s tt ❯tt♣♥♣s♦r♦P②stt♦♥r♠t♦♥ ①♣ér♠♥t ♠♦r t ②♠ s♦r ♠r t ♥ tPr ♦♥t ♦♥s ♥ α r♦♠♦r ♦r♦♥ P②s tt ❯ tt♣♥♣s♦r♦P②stt

❬❪ ❱st r♦♥ ❩ér ss♦♥ P♦♥ r♥ ♥ r♠st tt②♥♠s ♦ α♦r♦♥ r♦♠ ♥t♦ t♦♥ ♥ ♠♥ sttr♥ ♥r ♣rssr P②stt ♦ ❯ tt♣①♦♦r♣ss

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PP❳ P❯ ❱

❬♣♣rît ♣s ♥s ❪ r♣♥tr ❩ér ♥ ❱stPs♦♣♦t♥ts ♥♥ s♠♦r stts t ♥ ♣♣t♦♥ t♦r♠ αr♠ ♥ t♦r♠ P②s ❯ tt♣♥♣s♦r♦P②s

❬❪ ❱st r♥r ♥ ❩ér trtr ♥ tr♦♥♣r♦♣rts ♦ q ♦r♦♥ r♦♠ ♠♦r②♥♠s s♠t♦♥P②s ❯ tt♣♥♣s♦r♦P②s♦♥r♠t♦♥ ①♣ér♠♥t rs♥♥ ♥s t♥ ❱♦♥ ♥ Pr trtr ♦ q ♦r♦♥ P②s tt ❯ tt♣♥♣s♦r♦P②stt

❬❪ r♦t ❱st ♥ tr ♥strtr t♦♥♦ t ♠♥t♦r②st♥ ♥s♦tr♦♣② ♥r② 3 ♥tr♥t♦♥♦r♥ ♦ ♦r♥ P②ss ❯ tt♣①♦♦r

❬❪ ❱st r♦t ♥ ❩ér rst♣r♥♣st♦♥s ♦ t ♠♥t♦r②st♥ ♥s♦tr♦♣② ♥r② ♦ t♣♥t ♥ P②s ♦♥♥s ttr ❯ tt♣①♦♦r

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Page 112: Some ab initio tudies of the physical properties of materials

♣♣♥①

♥r ♦r♣②

❬❪ ❲ ♦♥ ♦ trs ♠str② ❲♦r ♥tPs♥ ♦ ♥♣♦r

❬❪ ♦♥s ♥ ♥♥rss♦♥ ♥st② ♥t♦♥ ♦r♠s♠ ts♣♣t♦♥s ♥ ♣r♦s♣ts s ♦ ♦r♥ P②ss

❬❪ P ♥♥♦③③ r♦♥♦ P P♦♥ ♥ r♦♥ ♥t♦

t♦♥ ♦ ♣♦♥♦♥ s♣rs♦♥s ♥ s♠♦♥t♦rs P②s

❬❪ r ❩r♦ r♦♥♦ ♦ ♥ ♦♥P♦♥♦♥ s♦t♥♥ ♥ s♣r♦♥tt② ♥ tr♠ ♥r ♣rssrP②s tt

❬❪ st ❱st ♥ ❱ ②tr ♥t♦ ♠t♦ ♦r ttr♦♥♣♦♥♦♥ sttr♥ t♠s ♥ s♠♦♥t♦rs ♣♣t♦♥ t♦ s♥ P P②s tt

❬❪ tt♦ ♥r t ❱st ♥ r♥s♦ r ♣r♦♥tt②r♦♠ ♦♣♥ ♦r♦♥ ♦sr P②s

❬❪ ♥ ♥ ❯ r♦ss ♥st②♥t♦♥ t♦r② ♦r t♠♣♥♥ts②st♠s P②s tt

❬❪ ❯ r♦ss ♥ ❲ ♦♥ ♦ ♥st②♥t♦♥ t♦r② ♦rq♥②♣♥♥t ♥r rs♣♦♥s P②s tt

❬❪ ♥ ♦tt r♥s♦ ♦tt t ❱st ❱r♦ ♥♦ ♥♥ ♥srst♥ ❲ssr ♥ ♦ ♦♥♥ ♥♦♦♦ ♦ ♥ ❲ ♦② ♦♥r♥ ♦♥trt♦♥ t♦ t①♥♦rrt♦♥ r♥ ♦ t♠♣♥♥t ♥st② ♥t♦♥ t♦r②P②s

❬❪ ♥ ♥♥ ♥ ♦ tr♦♥ ①tt♦♥s ♥st②♥t♦♥ rss ♠♥② ♦② r♥s ♥t♦♥s ♣♣r♦s ♦

P②s

Page 113: Some ab initio tudies of the physical properties of materials

PP❳ P❨

❬❪ ❲ ♦② ütr ♥ ♠ ♥r② ♦♣rt♦rs ♥①♥♦rrt♦♥ ♣♦t♥ts ♥ s♠♦♥t♦rs P②s

❬❪ ♥♥♦♦ ütr ♥ ♠ t♦♥ ♦ t ♦♥s♠♣♦t♥t ♥ ts s♦♥t♥t② ♦r ♠♦s♠♦♥t♦r P②s

❬❪ ♥ ♥ ♥qst ♦ stt ♣②ss ♦♠ ♣ ♠ Prss ❨♦r

❬❪ ♥ P②s

❬❪ rt ♥♥ ♦ ♥ ♥ P②s tt

❬❪ ♥t r② ♥ ♦♥ ♦r② ♦ ♦♣t s♦r♣t♦♥ ♥♠♦♥ ♥ s P②s

❬❪ ♥t r② ♥ ♦♥ ♣t s♦r♣t♦♥ ♦ ♥st♦rs♥ t tr♦♥♦ ♥trt♦♥ ♥ ♥t♦ t♦♥ P②s ttrs

❬❪ ♦♥ ♥ ♦ tr♦♥♦ ①tt♦♥s ♥ s♠♦♥t♦rs ♥♥st♦rs P②s tt

❬❪ ❱st ♥♥ ❱ ♥♦ P tts♥r ♥ ♦r②♦ ts ♥ t ♥s♦tr♦♣② ♦ t tr♦♥ ♥r② ♦ss s♣tr♠♦ tt♥♠ ♦① 2 P②s tt

❬❪ r♥♦♣♦♦s ♥♥ ♦ ♥ ❱st ♣t ♥ ♦sss♣tr ♦ r♦♥ ♥♥♦ts ♣♦r③t♦♥ ts ♥ ♥trt♥trt♦♥s P②s tt

❬❪ ♦tt ❱st ♥♥ ❱ ♥♦ ♥ ♥r♥ ♥t♦

t♦♥ ♦ t tr t♥s♦r ♦ ss s♣rtts P②s tt

❬❪ ♦tt ♠♠♣r ♥ ♥t♦ t♦♥s ♦ ♦♣t ♣r♦♣rts ♥

s♠♦♥t♦r s♣rtts P tss ❯♥rstà P t

❬❪ ♦tt ❱st ♥♥ ❱ ♥♦ ♥ ♥r♥ ♥t♦

♥ s♠♠♣r tr rs♣♦♥s ♦ s♣rtts P②s

❬❪ s t ❱st P♣♣ r♥ r ②♥t ♥ ♥♥ tr♦♥ strtr ♥ tr♦♥ ♥r②♦ss s♣tr♦s♦♣②♦ ❩r2 ③r♦♥ P②s

❬❪ ♦tt r♥ r♥♦♣♦♦s s ♦tt ❱ ♥♦ ❱st ♦ ♥ ♥♥ r♦♠ ♠♦s t♦ s♦s tr♦ ♦ ♦♥r♥ ♥trt♦♥s ♥t ♥t ♠

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PP❳ P❨

❬❪ s ♥ r♥ ❱r♥ r♥té t ❱st ♥ ♥♥ tr♦♥ ①tt♦♥s ♥t♦ t♦♥s ♦ tr♦♥ s♣tr♥ ♣♣t♦♥ t♦ ③r♦♥ ❩r2 tt♥ 2 ♥ ♣r♦s ♦① 2♦♠♣ t

❬❪ ♥ r ♥ ♦t♥ tr♦♥ s♦♥sst♥t❲ ♣♣r♦①♠t♦♥ ♣♣t♦♥ t♦ ♥ ♥ P②s tt

❬❪ r♥ ♥ t ♦rrét♦♥ ♥s trtr tr♦♥q s

♦s ♠ à ①② r① ♣♣r♦①♠t♦♥ ❲ t àP tss ♦ P♦②t♥q Ps r♥

❬❪ ♥ r♥ t ❱st ♥♥ ③qr♦ r♦tt♥ rrtt ①♥ ♥ ♦rrt♦♥ ts ♥ tr♦♥ ①tt♦♥♦ 2 P②s tt ♥ rrr♥s r♥

❬❪ ♥ r♥ t ❱st ♥ ♥♥ t ♦s♦♥sst♥② ♦♥ qs♣rts ♥ s♦s P②s

❬❪ st ❱ ②tr ♥ ❱st ♥tr② sttr♥ ♥ s ♥t♦ t♦♥ ♦ t t ♣r♠trs ♦r ♦♥t r♦ s♠t♦♥s♣♣ P②ss

❬❪ st ❱ ②tr ♥ ❱st ♠♣ ♥t♦ st② ♦ Γ − X

♥tr② sttr♥ ♥ s ♥r ♣rssr P②s

❬❪ ❱st Pr♦♣rétés rt♦♥♥s ♦r α t rr ♦r 4P tss ❯♥rsté Prs ❱ r♥

❬❪ t ❱st Pr♦♣rétés rt♦♥♥s ♦r α t rr ♦r4 ès ♦t♦rt ❯♥rsté Prs ❱ r♥ t r♣♣♦rt

❬❪ ♥r ♠♥ ♥ ♦rt s♥♥ s♣rr♠trs ♥s

❬❪ ❱st r♦♥ ❩ér ss♦♥ P♦♥ r♥ ♥ r♠st tt②♥♠s ♦ α♦r♦♥ r♦♠ ♥t♦ t♦♥♥ ♠♥ sttr♥ ♥r ♣rssr P②s tt ♦

❬❪ ❱st r♦♥ ❩ér ss♦♥ P♦♥ r♠st ♥ r♥ tt ②♥♠s ♦ ♦sr α♦r♦♥ ♥r ♣rssrP②s tt

❬❪ ③③r ❱st ss♦♥ r♦♥ ♥ ♥r ♦rs♦trtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr 4 ♦r♦♥ rP②s tt

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PP❳ P❨

❬❪ ③③r ❱st ss♦♥ r♦♥ ♥ ♥r ♦rs♦rrt♠ strtr ♥ rt♦♥ ♣r♦♣rts ♦ ♦sr 4 ♦r♦♥r P②s tt

❬❪ ❱st ss♦♥ r♦♥ ♥ ♦rs♦ t♦♠ strtr ♥rt♦♥ ♣r♦♣rts ♦ ♦sr α♦r♦♥ ♥ 4 ♦r♦♥ r♦♠♣ t

❬❪ ♥♥ ❲ ② ♥ ♦ P②s tt s réstts ♣♣r s♦♥t rr♦♥és ♦r♠ rr ♦r 12 st qs ♥①st♥t s♦♥ ♥♦s s

❬❪ r ❱st ♥ Pr t♦♠ strtr ♦ ♦sr 4♦r♦♥ r r♦♠ rst♣r♥♣s ♥②ss ♦ s♣tr P②s tt

❬❪ r♠ts ❱ ❱ tr③♥ ♦ ♥ ♠② ♥

❬❪ ♥♦ ♥ ❨ tt ❲ ss ❩ ❨ r② ♥ ❱ ♦♦③♥♦ tr

❬❪ ♥ ♥ ❩ strtr ♦t♦♥ ♦ ♦r♦♥r ♥t♦ t♦♥s ♣♣ P②s tt

❬❪ s♦ r ♥ t②♠❨♦s P②s

❬❪ ③ r③ ♥ ❨♦s♦♥ P②s tt

❬❪ ❱st st ♥ tr♥♥② ♦r♦♥ rs r♦♠ rst♣r♥♣s P②s ♦♥ r

❬❪ ❱♦r ❲ ♥rt ♥ s ②♥♠ ♦r ♦♦r♦♥ r ♣♣ P②s

❬❪ ♥ ❲ ② ♥ ♠r ♦♥ ♦③♠♦r♣③t♦♥ ♥ ♦r♦♥ r ♥

❬❪ ♦s s ♥ ❨ ❨♣ tr♥♥ ♦r♠t♦♥♦ r♦♥ ♥ ♦r♦♥ strs ♥ ♦r♦♥ r r♥ ②♥♠♥♥tt♦♥ ♣♣ P②ss ttrs

❬❪ ❳ ❨♥ ❩ ♥ ❩♥ ♦ ♥ ❨ ❩♥ ♦t♦ ② ♥ ❲ ♥ ♣rssr③t♦♥ ♠♦r♣③t♦♥ ♦s♥r②st ♦r♦♥ r P②s tt

❬❪ ❳ ❨♥ ❲ ♥ ❲ ♥ ♠♥ s♣tr♦s♦♣② ♦♣rssr♥ ♠♦r♣♦s ♦r♦♥ r ♣♣ P②s tt

❬❪ ❱ r♥té t té♦rq s ♣ss tt♥ P tss ♦P♦②t♥q Ps r♥

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PP❳ P❨

❬❪ r r ♥ t②♠❨♦s ❱♥ ♦♥tr♦ ♦αr♦♠♦r ♦r♦♥ ② tr♦♥ ♦♣♥ P②s ♦♥ ttr

❬❪ P ❯♠r t♥t ♥ r♦♥ r♥ t s③ ♣ t♥♥st②♥t♦♥ ♥ ♠♥②♦② ♣rtrt♦♥ t♦r②♦♥♠t

❬❪ ♠♥♥ ♥ ❱♥rt P②s

❬❪ ❲r tt r ♥ r♦♥ ♥t ♣♣r♦ t♦t♠♣♥♥t ♥st②♥t♦♥ ♣rtrt♦♥ t♦r② ♦r ♦♣ts♣tr♦s♦♣② P②s tt

❬❪ r r ♥ r ♥st② ♥t♦♥ t♦r② ♦ ttr ♦♥tt② ♦ ♠♦r s P②s tt

❬❪ ❲sr P②s

❬❪ r♥r ♥ ♦♥ P②s

❬❪ r P②s

❬❪ P ♦♥r ♥ ❲ ♦♥ P②s

❬❪ ❲ ♦♥ ♥ ♠ P②s

❬❪ ❲ Ptt Ps♦♣♦t♥t ♠t♦s ♥ ♦♥♥s ♠ttr ♣♣t♦♥s♦♠♣ P②s ♣

❬❪ ♥ ♥ t③ é♥q ♥tq t♦♥s r ♦s♦r t♦♥

❬❪ s♦♥ ss tr♦②♥♠s ♦♥ ❲② ♥ ♦♥s ♥ ❨♦r ♥ t♦♥ t♦♥

❬❪ P Pr ♥ ❨ ❲♥ P②s

❬❪ ♥ ♥ ❱♥ ♥t♠ ♦r② ♦ t tr♦♥ q♠r ❯♥rst② Prss ♠r

❬❪ ♦♥♦♠♦ r♥s ♥t♦♥s ♥ q♥t♠ ♣②ss ♦stts♥s ♣r♥r ❱r r♥

❬❪ ♥ ♥ ♥ ♥s t♦rs ❯♥♦♣ tr♦♥

stts ♣ ♣r♥r❱r r♥

❬❪ ❲ ❩ tr

❬❪ r tr t♦r② ♦ tr♦♥ ♥trt♦♥ ♥ s♦s Pr♦P②s ♦

❬❪ ②rts♥ ♦ P②

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PP❳ P❨

❬❪ ♦rs ♦tr ❲ rt ♥ ♦③♥r ♦

P②s

❬❪ ♦t♦♥ ♥ ♠t t♦rs ♥rr ♣②ss r♥♦♥Prss ①♦r

❬❪ t ♥ rt P②s tt

❬❪ ♦① ♥ P r P②s ♥♥

❬❪ rt ♣t s♦r♣t♦♥ s♣tr ♦ s♠♦♥t♦rs ♥ ♥st♦rs

♥t♦ t♦♥s ♦ ♠♥②♦② ts P tss ♦P♦②t♥q r♥

❬❪ rt♦♥ t♦r tr♦♥ ♥r②♦ss s♣tr♦s♦♣② ♥ t ♠r♦s♦♣P♥♠ Prss ❨♦r

❬❪ ❱ ♥♦ ♥ ♥♥ P②s tt

❬❪ st♥♥ r♥ ❲ ♦♠ ❱♦s P①t♦♥ ♥ ❲ ♥♥s P②s

❬❪ ♦ss ❲ ♥♦rt ♦tt P r♦♥ r②s♦♥ ♥❲ ♦♠ ♥st P②s ♦♥ r

❬❪ r♥ ss ❨ ❳ ♥ ❲❨ ♥ P②s

❬❪ ♣tr s♠ ❳ ♥t ♥ ♦ P②s tt

❬❪ r ♥ ♥ ♦ P②s

❬❪ r♠s t♥ ♥ P ♥ t ♥ strtr ♥ ts♦r♣t♦♥ s♣tr♠ ♦ 2 P②ss ttrs

❬❪ r♦♥ Prt ♦♠♠♥t♦♥

❬❪ ♥♥ ❱ ♥♦ ♦ ♥ ♥ P②s tt

❬❪ r♦♥ r♦♥♦ ♦rs♦ ♥ P ♥♥♦③③ P♦♥♦♥s ♥rt r②st ♣r♦♣rts r♦♠ ♥st②♥t♦♥ ♣rtrt♦♥ t♦r② ♦ P②s

❬❪ r ♥ ♦ P②s tt

❬❪ s♠♥ ❲ rs t ♥ rs ♠

P②s

❬❪ Pr ♥ r P②s

❬❪ P Pr r② ❱♦s♦ s♦♥ Prs♦♥ ♥ ♥ ♦s P②s P❲♥t♦♥

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PP❳ P❨

❬❪ P Pr r② ❱♦s♦ s♦♥ Prs♦♥ ♥ ♥ ♦s P②s P❲ ♥t♦♥

❬❪ tt r♥ ❱ ♥♦ ♥ ♥♥ ❯♥rst♥♥♦rrt♦♥s ♥ ♥♠ ♦① r♦♠ rst ♣r♥♣s P②s tt

❬❪ r♠♥♥ P♦tr② ♥st♥ ♥ ♦rs ②♥♠s♥ts ♥ ♦rrt♦♥ssst ♣rs tr♥st♦♥ ♥ ♦2 P②s tt

❬❪ ❲ tt trtr ♥ ♦♥♥ ♥ r②st♥ ♦r♦♥ ♥ 123♦r♥ ♦ P②ss ♦ tt P②ss

❬❪ ♠♠s t♥ rs♥r♥ ♥ P P♥rt♥ ♥②♥ tr♦♥♦♥t♥ r ♦r ♠r♦♣♦②r♦r♥s ♠t♦r♥s ♥ ♠t♦♥s ♦r♥ ♦ t ♠r♥

♠ ♦t②

❬❪ ♠♠s t♥ ♥ rs♥r♥ P♦②r♦r♥s ♥ ♠♥t ♦r♦♥♥s♣ rt strtr rt♦♥s ♥rs tr♦♥ rqr♠♥ts ♦r♥ ♦ t ♠r♥ ♠

♦t②

❬❪ ♠♥ P②s ♦②

❬❪ ♠s ♦② ❲s♦♥ ❲ rs ss♦♥ ♦t③ ♠ s ♥ P②s tt

❬❪ ♦r♦s♥ s♦♥ s ♥ ♠♥ ♦r♥♦ ♦②s ♥ ♦♠♣♦♥s

❬❪ ♥ ♦r♦s♥ P②s ♠

❬❪ ♦r♦s♥ s ♥ s♦♥ tr s ②♠♣ Pr♦

❬❪ rs♦♥ ♦r♦♥ ♦s ♦♥ Pr♦ ♦♠ P ❨♦r

❬❪ ♦r♦s♥ s ♥ ♠♥ ♦r♦♥ ♦s ♦♥ Pr♦♦♠ P ❨♦r

❬❪ r♥♥③♠ r♦ P♦♥♥♦ r♦t r ♥ r s♠♥t♦ ♠ P②ss ttrs

❬❪ r♥ P rí♦♥③ás ♥ ♦ P②s tt

❬❪ ③③r ❱tt♥ ♥ ♦♥ P②s

❬❪ ♥♦tt ❲ ♥ ♥ rst♣r♥♣s st② ♦ tstt② ♦ ♥ P②s

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PP❳ P❨

❬❪ ❨♥ ♥ ♦♥ P②s

❬❪ ②r ♦♥ ♦s♦♥ rör P ②r ♠ ♥rt ♥ ♥qst ❱♥ r s ♥st② ♥t♦♥ ♦r②r strtrs P②s tt

❬❪ s ♥ ❳ ♦♥③ rt ♥st② ♥t♦♥s ♣♣r♦s s♥t t♦♥♥t♦♥ tt♦♥ss♣t♦♥ t♦r♠ P②s ♦♥♥s ttr tr P②s ♥

❬❪ r ♥ ❱♥ ❱♦♦rs tt♦♥ss♣t♦♥ t♦r♠♥st②♥t♦♥ t♦r② ♦r♥ ♦ ♠ P②ss

❬❪ P rí♦♥③ás r♥♥③ r♥ ♥ ♦ ♥♦rrt♦♥ ♥t♦♥s♥s♣ ♣♣t♦♥ t♦ ♠trs ♥ ♦③s②st♠s ♦r♥ ♦ P②s ♠str②

❬❪ t r ♥ ♦r rss ♦s ♥r② rs ♦r ♥♦ s s♦st ② t ♦♥♥t♦♥ tt♦♥ss♣t♦♥ t♦r② P②s ♦♥♥s ttr tr P②s

❬❪ r ♥ r Prt ♦♠♠♥t♦♥

❬❪ ❲♦♠ ♥ ♦ ②♠♠tr②r♦♥ r②st strtr ♦♠♥t ♦r♦♥ t ♦ t♠♣rtr P②s

❬❪ ❲♦♠ ♥ ♦ ts ♣r♦♥stt♣r♣②s♠♦♠♣sP♣

❬❪ ♥ ♥ ❨ ❲♥ ②♠♥♦ rr♦② ♥ ❩ Psstt② ♥ α ♥ βr♦♠♦r ♦r♦♥ P②s ♦♥♥s ttr

tr P②s

❬❪ ♥ tt♥ ❯tt♥ ❲s ♥ ♦rtr♠♦②♥♠ stt② ♦ ♦r♦♥♥s♣ t r♦ ♦ ts ♥ ③r♦♣♦♥t ♠♦t♦♥ ♠ ♠ ♦

❬❪ ts ② ❨ ♦t♦♠ r ♥ ♠♣rt r②st ♥ ♥s s♠♦♥t♦r ♦r♦♥ rstt ♠♥t♦r♥ ♦ t ♠r♥ ♠ ♦t②

❬❪ ❯ ♠♥♥ ❲rt ♥ t③ ♦r♥ ♦ ♦②s ♥♦♠♣♦♥s

❬❪ ♥t s ♠♣ ♥ ♠♥ P②s

❬❪ ❯ ♠♥♥ ♥ ❲rt P②s tt ♦

❬❪ ❲rt ♠ ❯ ♠♥♥ ❯ ♠♣♥ ❲ ö♥ ♥ ♥ t rt② ♦ t r♠♥ s♣tr ♦ ♦r♦♥r s♦s♦r♥ ♦ ♦②s ♥ ♦♠♣♦♥s

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PP❳ P❨

❬❪ r♣tr s P♣s ♥ ♦♥t③ ♦r♦♥

♦s ♦♥ Pr♦ ♦♠ P ❨♦r

❬❪ ♥♥ ♠ r♠ ♦

❬❪ r③♦♥♦ ❨ r♦②♠ ♥ ❲t♥ ♠ ♦ ♣♥

❬❪ ♠♦♥ t P ss♦♥ ♥♦③③ rs ♥ qt tr

❬❪ ②♥r ♥ ♥♠♥ trtr ♦ 132 P②s

❬❪ r♦r ♥ rt♥s P②s

❬❪ ❲ st t strtr ♠♦ ♦s ♦r♠t♦♥ ♥r② s♥t t rs♣t t♦ ♦♠♣♦st♦♥ ♥t♦ ♠♦♥ ♣s α♦r♦♥ ♥s t ♦st ♦♥ ♠♦♥ strtrs t t s♠ r♦♥ ♦♥♥trt♦♥

❬❪ ❲ ②♠ P②s

❬❪ ❲rt ♥ ♥ t♦r ♥♦tör♥st♥ ♦r♦♥♦♠♣♦♥s ♦♠ ♣ ♣r♥r❱r r♥

❬❪ ❲rt s ♦♥r♥

❬❪ ❲ s r♠♦♠ s Prt ♦♦♠ t♦♥ ♥sttt ♦ t♥rs ♥ ♥♦♦② t t♦♥

❬❪ ♠t ♦r♥ ♥ ❱♥ rts♥ t ♦♦♠st♦♥ ♥ ♦r♠t♦♥ ♦ ♦r♦♥ r ♦r♥ ♦ t ♠r♥

♠ ♦t②

❬❪ ürs rqs t♦ts ♦rs Pr♦t st ♦♥t♥♥③ ss ♥ r♦ss P②s

❬❪ rqs ürs t♦ts Pr♦t ♦rs Pr♦t st ♦♥t♥♥③ r♦ss ♥ ss P②s

❬❪ ❩♦ t♦ ♦rs♦ ♥ r♦♥ ♥t♦ s♠t♦♥ ♦♣♦t♦♠ss♦♥ s♣tr♦s♦♣② ♥ s♦s ♣♥ ♣s♦♣♦t♥t♣♣r♦ t ♣♣t♦♥ t♦ ♥♦r♠♠ss♦♥ s♣tr ♦ ♥ P②s

❬❪ st ❱st ♥ ❱ ②tr ♥t♦ st② ♦ tr♦♥♣♦♥♦♥♦♣♥ ♥ ①t♦♥ ♥t ♥ s ♥r ♣rssr ♥ P♦r♥ ♦ ♠♥s♥

❬❪ P r r♠♥♥ ♥ ♠ r♠ ♦

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PP❳ P❨

❬❪ ♥ ♦t t♦rs Ps qr r♠s r♠ss♦♥ t♦♥ ♥sttt ♦ t♥rs ♥ ♥♦♦② trsrr②♥

❬❪ ❳ ❩♦ ♥ ❱♥rt P②s

❬❪ s ❨♠♦ ❨ r ♥ s tr

❬❪ r♥ t♦r ❩r♦♥ ♥s ♥ ❩r♦♥ ♥ ♥

♥♦♦② sr ❨♦r

❬❪ ❲tr P s ♥ ♣♣ r ♥ ♣

❬❪ ❱ ♦r♥t♥ ♥ r P②s tt

❬❪ Pt♥♦♠ rtr ♥ P ♥ P②s

❬❪ r♠ ♦t♥r ♥ ♥ P②s tt

❬❪ ♦r♥t ♥③ ♥ ï12 P②s

❬❪ r♠♥♥ ♥ ①♥r ♠♣

❬❪ r t r②st♦r

❬❪ P rt ♥ P rrs ♠ r♠ ♦

❬❪ ♦♦♠♦ ♥ ❩♥③♦tt♦ rst♣r♥♣s st② ♦ tstrtr ♥ st ♣r♦♣rts ♦ ③r♦♥ ♠tt Prt♦♠♠♥t♦♥