On the Possible Effect of the Vacancy Concentration on the Correlation Factor for Tracer Diffusion via Vacancy Mechanism

The effect of the vacancy concentration on the correlation factor has been investigated quantitatively. For a given vacancy concentration C v , the number of correlated jumps of a vacancy, n c , can be defined, and this number is used for the calculation of the correlation factor. The deviation of the correlation factor from the value corresponding to an infinitely dilute vacancy concentration is less than 1% for C v =10 -3 and less than 0.2% for C v =10 -4 . For usual experimental conditions, the correlation factor may be regarded as temperature independent.