Isolated anion vacancies and vacancy pairs were found to contribute to anion mass transport, as deduced from the anion tracer self-diffusivities in pure or doped (up to 2.5mol%Cd) specimens (table 3). The data were analyzed by using the Lidiard-Debye-Hückel theory. The effective activation energies and entropies were anomalously large; thus indicating the involvement of some phenomenon which was not included in the usual simple model.

Anion Self-Diffusion in AgCl and AgBr by Both Single Vacancies and Vacancy Pairs. A.P.Batra, L.M.Slifkin: Journal of Physics - C, 1976, 9[6], 947-58

 

Table 3

Diffusivity of 82Br in Pure and Cd-Doped AgBr

 

Temperature (C)

Cd (mol%)

D (cm2/s)

359.6

0

1.48 x 10-11

359.6

1.25

1.31 x 10-11

359.6

2.00

1.28 x 10-11

359.6

2.41

1.30 x 10-11

380.4

0

5.09 x 10-11

380.4

1.74

4.09 x 10-11

380.4

2.32

4.07 x 10-11

380.4

2.49

4.13 x 10-11

408.0

0

3.42 x 10-10

408.0

1.74

2.52 x 10-10

408.0

2.42

2.41 x 10-10

408.0

2.47

2.42 x 10-10