The porous-frit technique was used to investigate self-diffusion in molten samples. The data for temperatures ranging from 380 to 555C could be described by:

D (cm2/s) = 8.3 x 10-4 exp[-6.1(kcal/mol)/RT]

C.A.Sjöblom, J.Andersson: Zeitschrift für Naturforschung, 1968, 23a[2], 239-41