Question

2. A crystal of AgCl is cooled to temperature T = - 123°C. Calculate the number of Frenkel defects CEK_272 present in I m' of the crystal at this temperature. The material has a cubic unit cell of edge 0.555 nm 122- 72 that contains four Ag atoms. Assume that the interstitial atoms occupy any of eight tetrahedral sites in the unit cell. AHF - 2.69 x 10" J. Show all calculations. T:150k :0.555nm NSP AHE216909

Answer 1

Number Fenkel defeut is iven by NF N N* e2R no Fankel cefect Normallyupieitien by fhe mevin ton Pesition fo the N* No avaible 7ons -19 AH 2.69 X10 T N-4 N8 T - 123°C =ISOK -1२3न २न3 2.69X10 19 2 x8-314 S.65