Properties of alkaline earth sulfides, selenides and tellurides

Abstract

Values of the cohesive energy, atomisation energy, force constant, i.r. absorption frequency, Debye temperature, Grüneisen parameter, Anderson-Grüneisen parameter, and Rao-Keer constant of alkaline earth sulfides, selenides, and tellurides have been reported with the help of the three logarithmic interaction potential energy functions, suggested recently. The values of the electron affinity of S 2−, Se 2− and Te 2− ions have also been calculated from these potential functions. The average values obtained in kJ/mole, are: S 2− = 429; Se 2− = 495; Te 2− = 459. These values agree well with the available experimental data. The experimental values of the atomisation energy of these crystals have been computed by an indirect method using the thermochemical data. The experimental values of the cohesive energy of BeS and MgTe have also been reported and the values obtained, in kJ/mole, are: BeS = 3910; MgTe = 3148. These calculations further establish the validity of the new potential energy functions for heavier salts.