the structure factor for copper fcc lattice with one atom in [000] relative to the lattice point. r...
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rgijg
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The structure factor for copper
• fcc lattice with one atom in [000] relative to the lattice point.
• r1= [0,0,0], r2= [1/2,1/2,0], r3= [1/2,0,1/2], r4= [0,1/2,1/2]
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The structure factor for copper
• Result: • hkl even: F=fCu(1+1+1+1)=4fCu
• hkl odd: F=fCu(1+1+1+1)=4fCu
• h odd, k and l even: F=fCu(1-1+1-1)=0
• h and k odd, l even: F=fCu(1+1-1-1)=0
• Conclusion: hkl even or odd gives allowed reflections, hkl mixed gives forbidden reflections
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The reciprocal lattice for bcc iron?
• Body centered cubic lattice • One atom per lattice point, [000] relative to the lattice
point• What is the reciprocal lattice?