Henry Moseley (1887 -1915): t f th bi th f Xcentenary of the birth of X-ray

spectroscopy and the modern form of the periodic tableform of the periodic table

Russell Egdell

Inorganic Chemistry Laboratory, Oxfordandand

Trinity College ,Oxford

Phil hi l M i J l 1914Philosophical Magazine July 1914 Volume 27 Pages 703-713 1

Are the shallow core nd electrons involved in covalent bonding in ZnO, CdO and HgO? g g

The answer is given by O-K shell X-ray emission spectroscopy

he-

Conduction band EF

hO 2p valence band

Shallow core d state

+O 1s core level

?

C h l d i d b t i t di l l ti l hi h l ll it

Tony Orchard

Core hole decay is governed by a strict dipole selection rule which only allows on-site decay from O 2p states into the O 1s core hole.

Th O K h ll XES b th O 2 ti l d it f t tThus O K shell XES probes the O 2p partial density of states.Shallow metal core states only appear in oxygen K shell XES if they mix with O 2p

states.

O K shell XES of ZnO, CdO and HgO

x5 ZnOO 2p

0 12

0.14

Hg 5d5/2ty ra

tio

Zn 3d

0 08

0.10

0.12

Hg 5d

Hg 5d5/2

2p in

tens

it

x5 x5 CdO

Cd 4d

O 2p

0 04

0.06

0.08

Zn 3d

Hg 5d3/2

M n

d/ O

2

Kevin Smith formerly Dept.

14 15 16 17 18 190.02

0.04 Cd 4dC

orre

cted

y pPhysics at Boston University - now

head of Chemistry at Auckland

x5 HgOO 2p Atomic binding energy / eV

C

The shallow core nd intensity in O K shell XES is a direct measure of the extent of mixing of shallow core nd statesHg 5d measure of the extent of mixing of shallow core nd states

with O 2p states. These results explain the unique structure of HgO and why CdO has an indirect bandgap

Ph i l R i B 2003 68 165104/1 10Photon energy / eV

515 520 525 530 Physical Review B 2003 68 165104/1-10Chemical Physics Letters 2004 399 98-101Physical Review B 2005 71 235109

H M l i th T i it B lli l l b t i 1909

The definitive biography of Henry Moseley in the Trinity-Balliol laboratory circa 1909.

This is reputed to be the only known photograph of Moseley in a laboratory environment.

g p yMoseley was written

by John Heilbron, former student of Th K h y

He appears to be holding an X-ray tube, but did not start work in this area until 1912.

Thomas Kuhn.

Royal Society of Chemistry Historic Landmark Plaque

Royal Society of Chemistry National Landmark Plaque

Joseph Nordgren, ex student of Nobel Laureate Kai

National Landmark Plaque outside the Clarendon

Laboratory, Oxford. This was the first new-style RSC

Siegbahn and past Chairman of the Nobel Committee for Physics. Joseph gave a lecture on Moseley

on 24th September 2007“blue plaque” in Oxford.

on 24 September 2007at the RSC unveiling ceremony.

The late Harold Hankins CBE, F.R. Eng. was the first Vice Chancellor of UMIST.

His son Nick Hankins is a lecturer in Engineering at LMH

John Richardson is Chairman of the Western Front Association Ch hi d L hi B h d WFA M b hi T tCheshire and Lancashire Branch and a WFA Membership Trustee

6

John Gwyn Jeffreys FRS1809 - 1885

Henry Moseley FRS1801-1872

Solicitor and expert on molluscsClergyman, Naval Architect and Professor of Mathematics and Astronomy, UCL

Henry Nottidge Moseley FRS1844-1891

Linacre Professor of Anatomy, Oxford

Amabel Gwyn Jeffreys

Betty Moseley Margery Moseley Alfred AT Ludlow-Hewitt Henry Gwyn 1883-1899 1884-1952 1884-1979

Author of “Breeding Cows for Milk”

y yJeffreys Moseley

1887-1915

Henry C Ludlow-Hewitt Thomas NM Ludlow-Hewitt1912 - ? 1921 -?

Henry Moseley’s Education1896 – 1901 Summer Fields School, Oxford.

Henry Moseley s Education

1901 – 1906 King’s Scholar, Eton.

1905 Applies for Science Scholarship at Balliol. Family home at48 Woodstock Road1905 Applies for Science Scholarship at Balliol.

The only science scholarship has been promised to Julian Huxley.Rejects offer of Commoner place at Balliol

48 Woodstock Road

Rejects offer of Commoner place at Balliol.Offered Millard Science Scholarship at Trinity.

“I f d li ht d ith th d“I was of course delighted with the news and very content to go to Trinity”

(in letter to his mother, 15th December 1905)

“Any scholarship was better than none”(in letter to Harold Hartley at Balliol)

HGJM in 1906

1906 – 1910 Millard Scholar at Trinity.

Moseley’s entry inMoseley s entry in the College registerOctober 6th 1906

Moseley took a first in Mathematical Moderations and then decided to study

Physics rather than Chemistry.

Trinity had no Physics tutor –only D. H. Nagel, a Chemist to guide

hihim.

Most of his tutorials were farmed out to Idwal Griffiths a lecturer and later

Moseley’s Tutor D.H. Nagel

Idwal Griffiths, a lecturer and later Fellow of St. John’s.

The Oxford University Alembic Club Circa 1909

1907

1910

Moseley is second from right in back row 10

1907 Bow 1st Torpid 10st 9lb 1908 Stroke 2nd Eight 10st 7½ lb

1909 Stroke 2nd Eight 10st 8½lbs 1910 Stroke 2nd Torpid 11st 7lb

The 1910 2nd Torpid Crew

A.J. L. Carey (far right back row) later became wellrow) later became well

known as the author Joyce Carey.

L.R. E. Schmidt (seated 2nd

from right) was son of one of the directors of Krupps of

EssenEssen

E. L. Beale ( middle in back row) was killed in action at Longavesnes on 22 March 1918.

V. C. Downes (seated far right) died at St Omer on 18 October 1914, of wounds received in action.

E. H. Shears (cox, on ground to front) was killed in action at Boesinghe on 4 July 1917.

Albrecht Graf von Bernstorff (seated far left) a German Rhodes Scholar served as a diplomat inAlbrecht Graf von Bernstorff (seated far left), a German Rhodes Scholar, served as a diplomat in London in the years between the wars and was a vocal opponent of the Nazis during their rise to

power. He was executed in Lehrterstrasse prison in 1945.

Moseley’s “failure” in Schools

* July 1910 Awarded a 2nd class degree in Physics and not the 1st he had been expecting In 1910 there were eight 2nd class honoursbeen expecting. In 1910 there were eight 2 class honours degrees in Physics in the University but no 1st. Only one other honours degree in Physics had ever been awarded to a Trinity student and that was in 1887.y

* September 1910 Takes up Demonstratorship in Physics at University of Manchester working under Ernest Rutherford (Nobel g (Laureate in Chemistry 1908). Annual salary £125.

“My dear Mother,T l t t d t t I fi hti i ffi i tlTwo elementary papers today, not a great success. I was fighting inefficiently

against time. The heat is overpowering, and an owl squawked all night in the garden and kept me awake. -----”(in letter to his mother 17th June 1910)( )

“Dear Professor Rutherford,Thankyou for your letter informing me of my appointment. It will be a great

pleasure to work in your laboratory and after my failure in “schools” I consider myself verypleasure to work in your laboratory and after my failure in “schools” I consider myself very lucky to have got the opening which I covet. -----”(in letter to Ernest Rutherford, 17th July 1910) 13

Manchester Physics Department 1912

DarwinChadwick

Geiger Schuster Rutherford

MoseleyMarsden

y

Geiger and Chadwick in the Great WarGeiger returned to Germany in the autumn of 1912.

James Chadwick arrived in Germany in the autumn of 1913 to work with Geiger

Geiger was called to the front as an artillery officer on the outbreak of war in 1914

Chadwick was held as prisoner of war in the stable blocks f R hl b R f l t 1914 til th d fof Ruhleben Racecourse from late 1914 until the end of

the war

Rudimentary supplies of chemicals and apparatus wereRudimentary supplies of chemicals and apparatus were allowed into the PoW camp from mid 1915 onward

through the agency of Geiger.

Chadwick studied reaction between Mg metal and CO on exposure to light.

Both survived the war and Chadwick went on to discover the neutron.

Manchester September 1910 – October 1912

Demonstrator at University of Manchester. Finds teaching irksome and technical support limited. Also finds working on radioactivity mundane and repetitive.

“Remaking the apparatus took a long time as the Laboratory Assistant spent his time mending Rutherford’s motorcar”. (in letter to his mother, December 1910)

“Then there is a miserable lecture to Gas Engineers that I have been bullied into giving next term” (in letter to his sister Margery, December 1911)

“Today I was surprised to find a sad blunder in Rutherford’s latest paper --- I fearall his calculations are wrong, but when I demonstrated it to him heacknowledged his error, and declared that even if the calculations no longer did fitth th h i th th i i ht ll th ”the theory he is sure the theory is right all the same.”(in letter to his mother, October 1912)

B t orks on deca of radi m leading to a “radi m batter ” capable ofBut works on decay of radium, leading to a “radium battery” capable of producing a potential of 150,000V – the highest ever achieved at that time.

H G J Moseley The Attainment of High Potentials by the Use of RadiumH.G.J. Moseley, The Attainment of High Potentials by the Use of RadiumProceedings of the Royal Society 1913 87A 471-476

1901 1917 1908 1914 1915 1915 1922

1901 W.C. Rőntgen Awarded the first Nobel Prize in Physics for his work on X-rays in 1895.

1906 G.C. Barkla X-rays emitted from different elemental targets have different penetrating powers through metal foils Discovery of K and L rayspenetrating powers through metal foils. Discovery of K and L rays.

1909 E. Rutherford Backscattering of alpha particles from gold in the Geiger-Marsden experiment leads to the concept of the atomic nucleus and eventual development of the Bohr-Rutherford model of the atom

1912 M. von Laue Discovery of interference patterns when X-rays are transmitted through a crystalg y

1912 Moseley and Darwin begin their studies of X-rays, shortly after the Braggs. Moseley explains Laue diffraction using the concept of interference at meeting in Manchester on 1st November 1912of interference at meeting in Manchester on 1 November 1912

1912 W.L. Bragg Laurence Bragg explains Laue diffraction using Bragg equation at W.H. Bragg meeting in Cambridge on 11th November 1912. Paper introducing

the Bragg equation published in 1913the Bragg equation published in 1913

1913 N. Bohr First draft of paper introducing the Bohr model of the hydrogen atom discussed with Rutherford (and Moseley) at Manchester.

18th November 1912 Moseley tells his mother he is building apparatus to study X-rays

17th January 1913 Braggs report reflection of X-rays from mica crystal in letter to Nature

21st January 1913 Moseley and Darwin also report reflection of X-rays in letter to Nature

30th March 1913 WH Bragg tells Rutherford that sharp emission lines are observed at special angles in emission from Pt target. This enables Moseley and Darwin to find the sharp “characteristic“ emission lines which they hadDarwin to find the sharp characteristic emission lines which they had initially missed.

17th April 1913 The Braggs submit paper to Proc. Roy Soc. Published 1st July 1913

25th May 1913 Rutherford communicates paper from Darwin and Moseley to Phil. Mag.Published July 2013.

“Darwin and I are now trying to hustle a paper into the Phil. Mag. by the end of June ---- we have got Rutherford to coerce them. Bragg got in ahead of us --- and so the credit all belongs to him”L tt f M l t hi th 18th M 1913Letter from Moseley to his mother 18th May 1913

“Rutherford asked William to delay for a while the publication of his results so that Rutherford’s young men could repeat their experiments and announce the spectra also. My father acceded butyoung men could repeat their experiments and announce the spectra also. My father acceded but always felt it was not quite reasonable”Words of W.L. Bragg as quoted by John Jenkin in his biography of the Braggs 18

“Moseley was without exception or exaggeration the most brilliant man --- and the hardest worker I havemost brilliant man and the hardest worker I have ever met. There were of course no regular meals, and work often went on for most of the night. Indeed one of Moseley’s expertises was the knowledge of where one y p gcould get a meal in Manchester at 3 o’clock in the morning”.

Quotation from Charles Galton DarwinQuotation from Charles Galton Darwin

(Grandson of Charles Darwin and first to calculate the fine structure constant using Dirac’s model)fine structure constant using Dirac s model).

d)r(dV)r(2

dh

drdr4)r(dh

Proc. R. Soc. Lond. A 1913 88 428-438, (submitted 7th April 1913)

Philosophical Magazine 1913 26-XIV 216-232 Communicated by Rutherford 25th May 1913

22

H G J Moseley The High Frequency Spectra of the ElementsH.G.J. Moseley, The High Frequency Spectra of the Elements. Philosophical Magazine 1913 XCIII-26 1024-1034

Moseley was now employing a photographic method of measuring the X-ray spectra -and working on his own.

*November 1913 – June 1914

Moves back to Oxford with no paid position, presumably angling for the Chair in Physics which will become vacant in 1915 upon the retirement of Clifton.

Borrows apparatus including a Gaede pump from the Trinity/Balliol Laboratory toBorrows apparatus including a Gaede pump from the Trinity/Balliol Laboratory to complete his X-ray work in the “Electrical Laboratory”

(now the Townsend Building of the Clarendon).

26

2 2 2“My formula = (1/22 – 1/32) 0 (N-sn)2 for the L rays turns out to be triumphant, a great piece of

luck as I published it on the slenderest evidence- -

I take it that the formula means that the second ring is a 2h/2 ring . What the formula means physically

I cannot imagineI cannot imagine-----

I am going to look for an M series (1/32 – 1/42)-----Sketch in Moseley’s

It might interest you if you have any spare time to work out the properties of an atom (with 3 rings)”

letter to Darwin

(in letter to C.G. Darwin, 1st February 1914)

M-type X-rays were subsequently discovered by M. Siegbahn.

27

Philosophical Magazine 1914 27 703-713

Moseley’s LawMoseley’s original plot of atomic numberMoseley s original plot of atomic number

against square roots of frequencies of K and L X-ray emission lines. This plot established

most of the modern form of the periodic table.

Gaps correspond to elements 43 , 61 and 75 (Tc, Pm and Re)

are clearly identified. Between 66 and 72 there is some confusion

as to the numbering of the elements.

Moseley’s Law is that X-ray frequencies areMoseley s Law is that X-ray frequencies are given by:

A 0 (N-b)2

where N is the atomic number and b is a screening constant – equal to around 1 for K-type X-rays and about 7 4 for L-type X-raystype X-rays and about 7.4 for L-type X-rays.

A is given by (1/12 – 1/22) = 3/4 for K-type X-rays and (1/22 – 1/32) = 5/36 for L-type X-

rays.

0 is the Rydberg constant of atomic spectra.

Putting the later lanthanides in order

Th l th id i i “Hi h F S t f th El t P t II”The lanthanides as appearing in “High Frequency Spectra of the Elements Part II” Philosophical Magazine 1914, Volume 27 Pages 703-713

Putting the later lanthanides in order72 Cassiopeium Lutecium Celtium (Ct?) ?

71 Aldebarium Ytterbium Lutecium Lutecium

70 Thulium II Thulium II Neoytterbium (Ny) Neoytterbium (Ny)70 Thulium II Thulium II Neoytterbium (Ny) Neoytterbium (Ny)

69 Thulium I Thulium I Thulium Thulium

68 Erbium Erbium Erbium Erbium

67 Dysprosium Dysprosium Holmium Holmium?

66 Holmium Holmium Dysprosium Dysprosium

65 Terbium Terbium Terbium Terbium

64 Gadolinium Gadolinium Gadolinium Gadolinium

Letter to Georg von d Letter to Urbain JulyLetter to Georg von Hevesey 20th March

1914. 72 and 71 named as

2nd Phil. Mag paper April 1914.

72 and 71 named as claimed by Georges

Letter to W. H. Bragg

27th May 1914

Letter to Urbain July18th 1914 (sent from

Vancouver) after finding Ct is a

claimed by Carl Auer von Welsbach

claimed by Georges Urbain

27 May 1914 mixture of Lu and Ny

Based of study of chemically isolated sample ased o study o c e ca y so ated sa p eNo sample available

X-ray line visible as an impurity in erbium sample from Crookes 32

Result of analysis of five of Urbain’s samples of neoytterbium, lutecium and celtium, as indicated.

All the samples were mixtures of what would now be called ytterbium and lutetium

Henry Moseley June 1914 October 1914Henry Moseley June 1914 – October 1914

Travels to British Association for Advancement of Science Meeting in Australia via Canada to present his results with travel grant of £100via Canada to present his results with travel grant of £100.

Applies for Poynting Professorship of Physics at Birmingham on 8th October 1914 and receives strong letters of support from1914 and receives strong letters of support from

Rutherford, W.H. Bragg and Townsend. But the chair has been put on hold with the outbreak of the Great War on

28th July 1914.28 July 1914.

“Mr. H. Moseley’s experimental work on X-ray spectra has attracted the greatest interest and admiration on account not only of the value of the results g ybut on the rigour and brilliance of the methods”Testimonial Letter from W.H. Bragg, June 1914

“The results of these difficult investigations are of fundamental importance and have already exercised a strong influence on our ideas of the structure of atoms.”Testimonial Letter from E. Rutherford, June 1914

34

Moseley’s Military Career* October 1914 Commissioned as 2nd Lieutenant

in Royal Engineers on 10th October

* December 1914 Applies to be transferred to Royal Flying Corp but is over the

eight limit of 10st 7lb Tries and failsweight limit of 10st 7lb.Tries and fails to lose weight but in any case all transfers out of the New Army are forbidden by Kitchener in Januaryforbidden by Kitchener in January 1915

* February 1915 Attached to 13th Infantry February 1915 Attached to 13 Infantry Division and becomes aCommunications Officer of 38th Brigade38 Brigade

* June 1915 Posted to Gallipoli via Egypt as part of the British MediterraneanpExpeditionary Force.

35

The Gallipoli Campaign – Plan A

The Ottoman Empire entered the Great War in November 1914, cutting existing p , g gsupply lines to Russia and the Eastern Front.

Churchill’s Plan A was to ease stalemate on the Eastern Front by sending a Royal Navy fleet through the Dardanelles, securing the capitulation of Constantinople by y g g p p ythreatening the city with bombardment from gunships and finally re-opening the

Black Sea supply lines to the Russian port of Sevastopol.

Plan A

37

Plan B - ANZAC Chunuk Bair

April 1915 – July 1915

The Anzac operation aimed to capture high groundto capture high ground

inland from the eponymous Cove and bombard the Turkish forts along theTurkish forts along the

Narrows from this position. But stalemate developed with allied forces failing towith allied forces failing to

penetrate much more than a mile inland from the cove.

Plan C -The Anzac Breakout August 1915 g

F t li b f thThe Anzac enclave April-August 1915

Front lines before the Turkish counter offensiveThe Suvla plan

th

Moseley in Gallipoli* 9th July 1915 Lands at Helles and gains combat experience.

Withdraws to Lemnos in build up to the “August Offensive”.

* 6th August 1915 Lands at Anzac Cove as part of the reserves in support of the “Anzac Breakout”. The main objective is to capture Chanuk bair on the Sari Bair Ridge which dominates the peninsulaSari Bair Ridge which dominates the peninsula

* 9th August 1915 Moseley’s brigade under command of A.H. Baldwin finds itself the on “the F ” 300 d f th i bj ti f thFarm” 300 yards away from their objective of the front line trenches occupied by Allanson’s Gurkha Brigade on “Hill Q”. Allied forces nonetheless briefly occupy Chanuk Bair and the

Mustafa Kemel

nonetheless briefly occupy Chanuk Bair and the Hill Q saddle which overlook “The Narrows”.

* 10th August 1915 Baldwin’s brigade of 3,000 men overrun and obliterated by a force of 6 000 Turks who sweptobliterated by a force of 6,000 Turks who swept over Chanuk Bair led by Brigade Commander Mustafa Kemel (later Kemel Ataturk).Moseley was fatally shot.

“The Farm” from Chunuk Bair

Part of transcript (probably by his mother) of account of actions on “The Farm “ written by G.G. Chadwick (machine gunner in Baldwin’s brigade) dated 14th Aug 1915.

Archive for History of Quantum Physics (deposited in the libraries ofPhysics (deposited in the libraries of the University of California, Berkeley), p. 4.

“ The hill on our right was higher than ours and extended further back, therewas a deep mullah between the two hills. The Turks manned the hill andpumped lead into us from our right rear. This was my first experience ofpumped lead into us from our right rear. This was my first experience ofenemy fire without cover, and it was very unpleasant, most like a hailstormonly very much worse. They were not 300 yards from us. The General fellshot through the heart. Our signalling officer Moseley was killed and Balserg g g y(Brigadier Major) wounded in the arm. I saw the situation was prettyhopeless ---“

Gallipoli – the outcome

Following the Turkish counteroffensive on 10th

August 1915 stalemate was re establishedAugust 1915, stalemate was re-established. Eventually the Anzac enclave was evacuated in

December 1915 and Helles in January 1916.

Between April 1915 and January 1916 around 1,000,000 Allied and Ottoman troops were

involved in the Gallipoli campaigninvolved in the Gallipoli campaign.

Total casualties were estimated at over 500,000, including those who died or were evacuated due to g

illness (usually dysentery).

Overall the campaign cost 87,000 Ottoman dead p gand 43,000 Allied dead.

Of the 153 volunteers from Trinity College killed in World War I, 15 died in the Gallipoli campaign.

Ernest Rutherford, Nobel Laureate in Chemistry 1908

“Moseley was one of the best of the young people I ever had, and y y g p p ,his death is a severe loss to science “

“It is a national tragedy that our military organisation at the start of the war was so inelastic as to be unable with a fewthe war was so inelastic as to be unable, with a fewexceptions, to utilise the scientific services of our men, except as combatants in the firing line. Our regret for the untimelydeath of Moseley is all the more poignant because we recognisedeath of Moseley is all the more poignant because we recognise that his services would have been more useful for his country in the fields of scientific endeavour, rather than by the exposure to the chances of a Turkish bullet.”chances of a Turkish bullet.

Robert Andrews Millikan, Nobel Laureate in Physics 1923

“In a research which is destined to rank as one of the dozen mostIn a research which is destined to rank as one of the dozen most brilliant in conception, skilful in execution and illuminating in results in the history of science a young man of twenty-six years old threw open the windows through which we could glimpse the sub-atomicopen the windows through which we could glimpse the sub-atomic world with a definiteness and certainty never dreamed of before. Had the European War had no other result than the snuffing out of this young life that alone would make it one of the most hideous andyoung life, that alone would make it one of the most hideous and irreparable crimes in history.”

43

Would Moseley have won the Nobel Prize in Physics or Chemistry?Nobel Prize in Physics or Chemistry?

Svante August Arrhenius (Nobel Laureate in Chemistry 1903) was one of the most influential members of the Nobel Committees for Ph i d Ch i t t th t t f th 20th tPhysics and Chemistry at the start of the 20th century.

He nominated Moseley for the 1916 Prizes in both Chemistry and Physics but Moseley was killed before the Committees couldPhysics but Moseley was killed before the Committees could consider the nominations.

The prize can be awarded posthumously but only if the C itt h l t d it d lib ti b f th d thCommittee has completed its deliberations before the death.

Sources: Joseph Nordgren and Cecilia Jarlskog, both former chairs of the Committee for Nobel Prizes in Physics.both former chairs of the Committee for Nobel Prizes in Physics.Joseph Nordgren reckons Arrhenius always got his way

The only other Swedish Nobel Laureate in the Physical Sciences at the time y ywas Nils Gustaf Dalén who won the Physics Prize in 1912 for ”for his invention of automatic regulators for use in conjunction with gas accumulators for illuminating lighthouses and buoys”. He was blinded in an acetylene explosion in 1912 and could not attend theHe was blinded in an acetylene explosion in 1912 and could not attend the Nobel award ceremony. In 1922 he patented the design for the AGA cooker (AGA = Svenska Aktiebolaget Gasaccumulator)

Would Moseley have won the Nobel Prize in Physics? The 1924 Nobel Prize in Physics was awarded to Manne Siegbahn “for his discoveries and research in the field of X-ray spectroscopy”.

In the Presentation Speech the Chairman of the Committee for Nobel Prizes in Physics Professor A. Gullstrand,, states that:

“As the atomic number has proved to distinguish the elements better than the atomic weight, it has now attained the very greatest importance for atomic physics of the present day. Manne SiegbahnMoseley fell at the Dardanelles before he could be awarded the prize, but his researches had directed attention to the merits of Barkla, who consequently in 1917 was proposed for the Nobel Prize, which was awarded to him without delay.”

No Physics Prize was awarded in 1916 – the only year when a Physics Prize was not awarded during the1914-1918 war.

Barkla received a single (and late!) nomination for the Nobel Prize in Physics – from Rutherford Technically the nomination

Kai M. SiegbahnPrize in Physics – from Rutherford. Technically the nomination was only valid for the 1918 prize, but Barkla was awarded the 1917 prize.

Nobel Prize in Physics1981 45

Moseley’s Scientific Legacy

* His work was critical in development of the Bohr model of the atom and the subsequent development of quantum mechanics leading to currently accepted models for the structure of atoms, molecules and solids. This underpins almost all chemistry and physics.

"You see actually the Rutherford work [the nuclear atom] wasYou see actually the Rutherford work [the nuclear atom] was not taken seriously. We cannot understand today, but it was not taken seriously at all. There was no mention of it any place. The great change came from Moseley." (Niels Bohr 1962)

* Established the concept of atomic number leading the modern form of the periodic table. Paved the way for the discovery of seven new elements unknown in 1914seven new elements unknown in 1914.

* Established the experimental technique of X-ray emission spectroscopy as a means of chemical analysis. This technique and the related techniques of X-ray photoelectron spectroscopy (XPS), core level electron energy loss spectroscopy (EELS) and X-ray absorption spectroscopy (XAS) still continue to be very important to this dayvery important to this day.

46

The modern periodic tableGaps in Moseley’s compilation

Further elements unknown

Artificial radioactivetrans-uranic elements

in 1914

trans-uranic elements

1917 Protactinium Pa (91) 1923 Hafnium Hf (72) 1925 Rhenium Re (75)1937 T h ti T (43) 1939 F i F (87) 1940 A t ti At (85)1937 Technetium Tc (43) 1939 Francium Fr (87) 1940 Astatine At (85)1945 Promethium Pm (61)

The controversy surrounding element 721907 Georges Urbain claims to have isolated “celtium” from samples of ytterbia

and publishes results in 1911. He presumes it is a rare earth.

1914 M l di th t U b i ’ l f lti i i t f l t i1914 Moseley discovers that Urbain’s sample of celtium is a mixture of lutecium and neoytterbium

1920 Urbain continues to hanker after celtium as a rare earth and working with Dauvillier claims to observe X-ray lines characteristic of the element. No one else – including Manne Siegbahn - can see the lines.

1923 Following suggestions from Bohr and others that element 72 is in the zirconium group Dirk Coster (Danish) and Georges von Hevesey (Hungarian) find X-ray lines of element 72 in many samples of the mineral zircon from Norwegian geological museums. They proposed to name the

l t h f i ft th L ti f f C h h th knew element hafnium after the Latin form for Copenhagen where they work.

1923 “We adhere to the original word Celtium given to it by Urbain as a representative of the great French Nation which was loyal to us throughout the war. We do not accept the name that was given it by the Danes who only pocketed the spoils of war.”W.P. Wynne writing an editorial in Chemical News

1924 Chemically pure sample of Hf metal obtained by van Arkel and de Boer 48

The naming of element 431909 Masatka Ogawa claimed to have isolated element beneath Mn in periodic

table and proposed to call it Nipponium. He may have isolated Re.

1924 Bosanquet and Keeley claim to have observed X-ray lines characteristic of element 43 and proposed that it should be called Moseleyum. Support for the proposal appears in both Nature and Science Magazine. But discovery f th l t i t b t ti t dof the element is not substantiated.

1936 Carlo Perrier and Emilio Segre working in Palermo find X-ray lines characteristic of element 43 in scrap Mo material from Ernest Lawrence’scharacteristic of element 43 in scrap Mo material from Ernest Lawrence s cyclotron and propose to name the element Panormium after the classical name of Palermo – Panormus.

1937 H f Pittb h t th i t l t 43 M l1937 Hamer from Pittburgh mounts another campaign to name element 43 Moseleyum

1947 Element 43 named Technetium after the Greek τεχνητός = artificial.

The idea that no element was named after an individual until the transuranics emerged is wrong. Samarium was named after its extraction from the Russian mineral Samarskite .

Samarskite itself was named in recognition of Vasili Samarski-Bykhovets - who as chief of staff ofSamarskite itself was named in recognition of Vasili Samarski-Bykhovets - who as chief of staff of the Russian Corps of Mining Engineers allowed German mineralogists Gustav and Heinrich Rose

to study mineral samples from the Urals.

X-ray spectroscopy 100 years onX ray spectroscopy 100 years on

Portable hand held X-ray fluorescence (aka X-ray

emission) instruments are

The Curiosity Mars Probe incorporates two different X-ray emission spectrometers: the

APXS alpha particle excited X-ray now used routinely by mining

surveyors, scrap metal dealers etc. etc.

spectrometer mounted on the end of a robotic arm and the ChemMin X-ray analyser which measures both powder diffraction and X-ray

emission of powder samples using a cobalt Xemission of powder samples using a cobalt X-ray tube.

50

X-ray spectroscopy 100 years ony y yMost recent work with

soft X-ray XES is ybased on grating

monochromators with design principles defined by Ulrich

X-rays from a synchrotron undulator beamline are used to eject the inner electrons.

defined by Ulrich Gelius and Joseph

Nordgren

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X-ray emission spectrometersy

2007 19132007 1913

X-ray emission beamline at thebeamline at the

ALS synchrotron, Berkeley, California

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Some frontiers in X-ray spectroscopyMeasurement of photon-in photon-out resonantinelastic X-ray scattering spectra with energyresolution less than the core hole lifetime whenphoton energy is close to core threshold. Spectraare 3d-3d excitations in MnO measured on Springare 3d-3d excitations in MnO measured on Spring8 with 100 meV energy resolution.Review of Scientific Instruments 83, 013116 (2012)

Atomically resolved core shell energy loss spectraf S TiO (001) d i J l JEM ARM200Fof SrTiO3(001) measured in Jeol JEM-ARM200F

aberration corrected analytical electron microscope.

Temporal resolution approaching the femtosecond timescale using 4th generation X-ray lightsources. Figure shows emission spectra of Al indifferent charge states measured on LCLSNature 482 59 (2012). SM Vinko, JS Wark et al.

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"Those heroes that shed their blood and lost their lives... you are now lying in the soil of a friendly country. Therefore rest in peace. There is no difference between y y pthe Johnnies and the Mehmets to us where they lie side by side here in this country of ours... You, the mothers who sent their sons from far away countries wipe away your tears. Your sons are now lying in our bosom and are in peace. Having lost their lives on this land they have become our sons as well."

Words of Kemel Ataturk read by Atilay Ersan - the Minister Counsellor of Turkey to the UK - on the occasion of the RSC plaque unveiling ceremony on 24/09/2007.