Crystal structure and electrical properties of Gd$_x$Mn$_{1-x}$S и Ti$_x$Mn$_{1-x}$Se solid solutions

Regions of the existence of sulfide Gd$_x$Mn$_{1-x}$S and selenide Ti$_x$Mn$_{1-x}$Se solid solutions have been identified. Their electrical and thermoelectric properties have been studied in the temperature range 80–900 K. It has been established that the substitution of Gd$^{2+}$ and Ti$^{2+}$ ions for Mn$^{2+}$ cations initiates reversal of the type of charge carrier with respect to the starting compounds MnS and MnSe. The cation substitution in solid solutions brings about a change from the hole conduction ($\alpha>$ 0) characteristic of the manganese monosulfide and monoselenide to the electronic conduction ($\alpha<$ 0).