LATTICE VIBRATION SPECTRA OF A4BX6 GROUP CRYSTALS.

Autor: Kashuba, A. I., Solovyov, M. V., Maliy, T. S., Franiv, I. A., Gomonnai, O. O., Bovgyra, O. V., Futey, O. V., Franiv, A. V., Stakhura, V. B.
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Zdroj: Journal of Physical Studies; 2018, Vol. 22 Issue 2, p1-5, 5p
Abstrakt: We report on an X-ray diffraction study of A4BX6 (Tl4HgI6 and Tl4CdI6) group crystals. Structure data and atomic coordinates have been obtained by Rietveld method. The compounds of Tl4HgI6and Tl4CdI6 are isomorphous with each other and crystallize in a tetragonal lattice with the space group of P4/mnc. The results of the infrared and Raman spectra of Tl4HgI6and Tl4CdI6 crystals are present. On the basis of a factor group analysis and phonon frequencies calculated for Tl4HgI6and Tl4CdI6, the relations between the vibrational spectra and the crystal structures have been determined. Moreover, the distribution of vibrations for symmetry classes of single crystals and the selection rules for vibrations in the infrared absorption and Raman spectra are obtained. Phonon modes frequencies and their origin determination are based on Raman scattering data. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index