In A _ x B _ y crystal structure, A atoms occupied all octahedral as well as all tetrahedral voids and B atoms are at FCC centres. What is the formula of compound A _ x B _ y .

Step-by-step solution

Number of octahedral voids = x (where x = total number of atoms in the rinit cell) Number of tetrahedral Voids =2 x Total number of ' A ' atoms =x+2 x=3 x Since all 'B' atoms occupy all the FCC centres:- Total number of 'B' atoms = [6 1 2 ]+ [8 1 8 ]=4 x=4 so number of ' A ' atoms =3 x=3 4=12 So, the formula will be A₁₂ B₄ or A₃ B