Thermodynamic properties of chalcogenide and pnictide ternary tetrahedral semiconductors

Abstract

In this paper, we present thermodynamic properties such as heat of formation, heat of fusion and entropy of fusion for chalcopyrite structured solids with the product of ionic charges and nearest neighbour distance d (Å). The heat of formation (∆Hf) of these compounds exhibit a linear relationship when plotted on a log-log scale against the nearest neighbour distance d (Å), but fall on different straight lines according to the ionic charge product of the compounds. On the basis of this result two simple heat of formation (∆Hf)heat of fusion (∆HF), and heat of formation (∆Hf)entropy of fusion (∆SF), relationship are proposed and used to estimate the heat of fusion (∆HF) and entropy of fusion (∆SF) of these semiconductors. We have applied the proposed relation to AIIBIVC2 V and AI BIIIC2 VI chalcopyrite semiconductor and found a better agreement with the experimental data than the values found by earlier researchers. The results for heat of formation differ from experimental values by the following amounts: 0.3% (CuGaSe2), 6.7% (CuInSe2), 5% (AgInSe2), 5% (ZnGeP2), 6% (ZnGeP2), 0.4% (ZnSnP2), 0.7% (ZnSiAs2), 2.6% (ZnGeAs2), 1.2% (ZnSnAs2), 3.8% (CdGeP2), 6.4% (CdGeAs2), the results for heat of fusion differ from experimental values by the following amounts: 2.6% (CuGaS2), 0.6% (CuInTe2), 6% (ZnGeAs2), 8.8% (ZnSiAs2) and the results for entropy of fusion differ from experimental values by the following amounts: 6% (CuInSe2), 8% (CdSiP2).