Hiroshi HirashimaD. AraiTetsuro YOSHIDA
The dc conductivities (α) of PbO‐P 2 O 5 ‐V 2 O 5 glasses containing up to 80 mol% V 2 O 5 were measured at T = 100°C to T = 10°C below the glass transition temperature. Dielectric constants at 1 MHz, densities, and the fraction of reduced V ion were measured at room temperature. The conduction mechanism of glasses containing >10 mol% V 2 O 5 was considered to be small‐polaron hopping, as previously reported for other vanadate glasses. The temperature dependence of α was exponential, with α= (αo/ T ) exp(− W/kT ). When the V 2 O 5 content was ≥50 mol%, W decreased and α increased with increasing V 2 O 5 content, and the adiabatic approximation could be applied. In the composition range between 10 and 50 mol% V 2 O 5 , α increased with increasing V 2 O 5 content, but W varied little. In this region, the hopping conduction was characterized as nonadiabatic. The effect of dielectric constants and V ion spacing on W is discussed.
Hiroshi HirashimaKOTA NISHIITetsuro YOSHIDA
M. Nasir KhanE.E. KhawajaD. SAVEA. A. KutubC. A. Hogarth
D. ChakravortyA. R. HaranahalliD. Kumar