Representative hybrid model used for analyses of heat capacities of group-IV, III–V, and II–VI materials

摘要

Characteristic non-Debye features inherent to the dispersionrelated hybrid model, which had been devised for the sake of physically adequate representations of isobaric heat capacities of semiconductor and wide band gap materials, are demonstrated and discussed in some detail. We perform least-meansquare fittings of low- and high-temperature C_p(T) data sets that are available for group-IV materials (diamond, Si, Ge, 3C-SiC), III–V materials (BN, BP, BAs, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InP, InAs, InSb), and II–VI materials (ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe). The simulations of the C_p(T) data sets under study, particularly with respect to the cryogenic region, are graphically represented, and existing data deficiencies are discussed. Important by-products of the fittings are presented within the frame of Supporting Information (online at: www.pss-b.com). There are given in tabulated form the characteristic phonon energies, ε_P(m), for integral orders, m=-2, -1, 0, 1, 2, and 4, including further dispersion-related parameters like average phonon temperatures, QP, dispersion coefficients,DP, and high-temperature limiting values of Debye temperatures,QDh(1). Furthermore, basing on comprehensive calculations of the Cp(T) dependences from absolute zero up to room temperature, we provide representative values of entropies, Sp(T), enthalpies, H_p(T)-H_p(0), and Gibbs free energies, G_p(T)-G_p(0), for the frequently considered reference point, T_r=298.15 K, the accurate knowledge of which is indispensable for possible high-temperature continuations of these standard thermodynamic functions within the frame of the commonly used thermo-chemical formalism.