THE VIBRATION-SPECTRA OF THE SINGLE-CRYST ALS SR3GA2GE4O14

Results of the investigation of Sr3Ga2Ge4O14 monocrystals by vibration spectroscopy methods are presented. The interconnection between the l attice structure and macroscopic characteristics of the material is es timated. It is shown that the lattice vibration in the low-frequency r ange is formed mainly from vibration of the bond Sr - O (50 - 250 cm(- 1)) and from Ge - O terminal vibrations of GeO4 tetrahedron complexes (250 - 450 cm(-1)). The latter from a 2d structure and could be consid ered as local vibrators. The range of 450 - 900 cm(-1) corresponds to the frequencies of vibrations of Ge(2d) - O - Ge(3f) and Ge(1a) - O - Ge(3f). The effects of the structural disordering of Sr3Ga2Ge4O14 mono crystals for the Raman and IR spectra are analyzed.