The a.c. conductivity for the TeO2-P2O5 glassy system was measured in
the temperature range 300-573 K and in the frequency range 100 Hz to 1
0 kHz. The a.c. conductivity sigma(omega) increased with frequency acc
ording to the relation sigma(omega)alphaomega(s). The frequency expone
nt s was found to decrease with increasing temperature. The compositio
n dependence of the conductivity was also investigated. The density of
states was also calculated using the Elliott model. The a.c. conducti
vity increased over the studied temperature range. The obtained experi
mental data have been analysed with reference to various theoretical m
odels. The analysis shows that the correlated barrier hopping (CBH) mo
del is the most appropriate mechanism for conduction in the TeO2-P2O5
glass system.