The coalescence of Au grains (5 x 10-5cm diameter) on the (100) surfaces of single crystals was studied by means of electron microscopic analysis. On the basis of the results, it was calculated that the surface diffusivity of Au, at temperatures of 370 to 450C, ranged from 10-13 to 10-11cm2/s and could be described by:

D (cm2/s) = 5 x 104 exp[-52.0(kcal/mol)/RT]

Diffusional Coalescence of Metal Grains on Non-Metal Substrates. Y.E.Geguzin: Fizika Tverdogo Tela, 1970, 12[7], 1953-62