No abstract

No abstract

The electrical properties of a lithium heptagermanate (Li 2 Ge 7 O 15 ) crystal have been studied in DC and AC measuring fields at temperatures from 500 to 700 K. In a DC field, a substantial decrease of elec trical conductivity σ with time has been detected. On the basis of kinetic dependences σ(t), estimates of the charge carrier diffusion coefficient D have been obtained. In the frequency range 10 1 -10 5 Hz, the spectra of complex impedance ρ*( f ) have been measured. The analysis of diagrams in the complex plane (ρ'' -ρ') has been performed within the equivalent circuit approach. It has been shown that, in the considered temperature and frequency intervals, the electrical properties of Li 2 Ge 7 O 15 crystals have been determined by the hopping conduction of interstitial lithium ions A Li and accumulation of charge carriers near the blocking Pt elec trodes.

No abstract

No abstract