Determination of point defect parameters from silver diffusion data

Abstract

Seeger (1972) has analysed self diffusion data for a number of face-centeredcubic (f.c.c.) metals and has reported single and divacancy activation energies. Q ₁ and Q ₂, and frequency factors, D ₁₀ and D ₂₀. We have carefully examined the Rothman, Peterson and Robinson (1970) data for silver in order to assess the confidence which can be placed in the results published by Seeger. We find that the data can be equally well fitted by a wide range of parameters. Q ₁ lies between 1.82 and 1.95 eV and D ₁₀ between 0.1 and 0.5 cm²/sec. The ranges of equally good values of Q ₂ (2.25-2.75 eV) and D ₂₀ (3-300) are so great that these numbers, as determined from diffusion data in silver, are meaningless. Divacancy parameters determined for other f.c.c. metals are even less reliable.