Mn$_{0.1}$Ag$_{0.9}$In$_{4.7}$S$_{7.6}$ single crystals: Crystal structure, band gap, and thermal expansion

Mn$_{0.1}$Ag$_{0.9}$In$_{4.7}$S$_{7.6}$ single crystals are for the first time grown by the Bridgman method (vertical variant). The single crystals crystallize in the cubic spinel structure. The band gap of the single crystals is determined from the transmittance spectra in the region of the fundamental absorption edge at temperatures of $T$ = 295 and 80 K. Thermal expansion is studied by the dilatometric method in the temperature range 80–500 K. The coefficients of thermal expansion, the Debye temperatures, and the rms (root mean square) dynamic displacements of atoms are calculated.