Metal-glass-metal (MGM) thin film devices are prepared using vacuum deposit
ion of Sb2Pb1Se7 compound. The variation of ac conductance as a function of
thickness of films, temperature and frequency is studied. The observed cha
racteristics are explained on the basis of Co-related Barrier Hopping (CBH)
of bipolaron. It is shown that the theoretical curve generated using the f
irst order approximation gives excellent fitting with the experimental curv
e.