Purpose. The purpose of this research was to expand the study of the effect of temperature on the optical properties of AsXS1−x glasses and to compare the experimental data dn/dT = f(λ) with those calculated using Wemple and Di-Domenico single effective oscillator model. Methods. The refractive index was measured by a prism method. Plane parallel slabs with thicknesses of ∼1 mm were cut from synthesized bulk samples. The sample prisms had refracting faces with areas of 5×10 mm and angles between them of ∼ 10°-15°. The refracting angles of the prisms were determined on a LOMO G-1.5 goniometer. The temperature was measured with a copper-constantan thermocouple to within ±0.5 K. The error in the refractive index n over the entire observed spectral range was ±2·10–4. Results. The dispersion of the refractive index n(λ) of AsXS1−X glasses was studied in the concentration range from X = 0.20 to X = 0.40 of five samples in the temperature range from 80 to 370 K at wavelengths from 1.0 μm to 2.3 μm. The experimental results of n(λ) of AsXS1−X glasses were described in terms of the Wemple–Di-Domenico single effective oscillator model. The expression of the spectral dependence of the temperature increment of the refractive index (dn/dT) is obtained, according to which the spectral dependence of this parameter was calculated. Conclusions. Based on the experimental results, the concentration dependence of the refractive index are explained using the Lorentz-Lorentz formula. It is shown that dn/dT changes the sign in the region λ ∼ 0.96 μm, which agrees with the experimental data. In the area of transparency of the studied materials, dn/dT is negative. It was concluded that temperature change of the refractive index for As-S glasses depends mainly on the electron-phonon interaction, the magnitude of which decreases with increasing sulfur concentration

Keywords: glassy, synthesis, refraction, refractive index, single-oscillator model, energy of electronic oscillator, dispersion energy, temperature