Double Davydov resonance in the vibrational spectra of Tl3AsS4 and Tl3PS4 crystals

SYRBU, N. N.; KRASOVSKY, V. T.

Double Davydov resonance in the vibrational spectra of Tl3AsS4 and Tl3PS4 crystals

SYRBU, N. N.; KRASOVSKY, V. T.

URI: https://doi.org/10.1016/0921-4526(94)00223-I
http://repository.utm.md/handle/5014/12289

Date: 1995

Abstract:

Raman spectra of Tl3AsS4 and Tl3PS4 have been investigated at 300 and 77 K. The vibrational modes Ag, B1g, B2g and B3g are determined. The vibrational mode splittings caused by Davydov resonances are determined. Infrared reflectivity spectra of Tl3AsS4 and Tl3PS4 crystals have been investigated for the polarizations E∥a, E∥b and E∥c in the range 50–4000 cm−1. Reflectivi spectra contours are calculated and the main vibrational mode parameters are determined. The effective ionic charges of the anions and cations of the crystals are determined.