The product of conductivity and temperature was given by:

σK (SK/cm) = 3.8 x 103 exp[-0.190(eV)/kT]

for the β-phase at temperatures of between 90 and 235C, and by:

σK (SK/cm) = 3.7 x 103 exp[-0.091(eV)/kT]

for the α-phase at temperatures of between 235 and 500C.

J.G.Vlasov, J.E.Ermolenko, B.A.Nikolaev: Elektrokhimiya, 1981, 17[10], 1448-53