2. Crystal Structure

2 a sinθλ = ——————√h 2 + k 2 + l 2λ 2 (h 2 + k 2 + l 2 )sin 2 θ = ———————4a 2sin 2 θ A h 2 A + k 2 A + l 2 A——— = ———————sin 2 θ Β h 2 B + k 2 B + l 2 BMiller indices of the diffracting planes for BCCand FCC{hkl} Σ[h 2 + k 2 + l 2 ] FCC BCC{100} 1 ….. …..{110} 2 ….. 110{111} 3 111 …..{200} 4 200 200{210} 5 ….. …..{211} 6 ….. 211first two sets of diffraction planesFCC {111) and {200}sin 2 θ A h 2 A + k 2 A + l 2 A——— = ——————— = 0.75sin 2 θ Β h 2 B + k 2 B + l 2 B22