Dielectric relaxation in crystals of weak ferroelectric Li2Ge7O15 in the range of ferroelectric phase transition

The study on the ε dielectric permittivity in the vicinity of ferroelectric phase transition of the Li2Ge7O15 crystals, activated by the Ni ions, is carried out. It is shown that introduction of Ni quenches dielectric anomaly and essentially decreases the transition temperature. The temperature hysteresis of the ε(T) behavior is identified for nominally pure and alloyed by Ni Li2Ge7O15 crystals near the transition point (Tc)