Polyassociative thermodynamical model of A2B6 semiconductor melt and P-T-X equilibria in Cd-Hg-Te system: 1. Phase equilibria in initial two-component systems. Hg-Te system

Abstract

In the framework of the theory for associated solutions comprising several complexes of various compositions in a liquid phase, analyzed are phase equilibria in Cd-Hg-Te systems. Checking this theory as to the description of phase equilibria in a system as well as a search of model thermodynamic parameters were performed by the way of sequential computer processing the respective experimental results for initial two-component materials. Hg-Te system was chosen as the first model one. It was ascertained that HgTe, HgTe 2 and Te are dominating complexes in the liquid phase of this system. Determined were the complexcreative parameters in the liquid phase. As to P-T-X equilibria in Hg-Te system, we reached a satisfying accordance between calculation and experimental data.

Polyassociative thermodynamical model of A2B6 semiconductor melt and phase equilibrium in Cd-Hg-Te system: Optimization of the thermodynamical functions of the model and quasi-binary structural diagram of Cd-Hg-Te system

“…Let us remind, that the increase of this parameter from 9.25 up 14 e.u. during description of the X T p − − equilibrium in the mentioned system enabled to achieve good correspondence of the calculations to the experiment in [1]. The analysis of the phase equilibrium in the related Cd-Te system has shown, that variations of such type are not necessary for the description of the pressure of the metallic component in this system.…”

“…0 . 14 HgTe = Δ F S unchanged and corresponding to the experimental data [4], despite the decrease of the accuracy in the description of mercury pressure in the system [1]. Such reevaluation of the temperature dependencies of dissociation constants in Hg-Te systems, when in the melt 3 2 Te Hg , Te Hg 2 complexes are present was performed in the present work.…”

“…In our previous works [1,2] it was shown, that the polyassociative model of the melt can be successfully applied for the description of the phase equilibrium in binary 6 2 B A systems. In this work the obtained thermodynamical information on the thermodynamical properties of the initial binary components of Te Hg Cd x 1 x − solid solution will be disseminated on the analysis of the structural diagram of ternary Cd-Hg-Te system.…”

“…Mentioned above at first place refers to the melts associative composition of this related systems. According to the calculations [1], Hg-Te melt energetic state can be modeled under its consideration as consisting from the next complexes: HgTe, 2 2 Te , HgTe…”

“…One of the perspectives of polyassociative solutions model application to the description of phase equilibrium was connected with the decrease of the thermodynamical parameters number, the experimental evaluation of which is difficult or simply impossible [1]. In this respect it seems reasonable to evaluate the possibility of minimization of model parameters number at the cost of the lowering of the number of considered associates in liquid phase.…”