Calculations of the thermodynamic properties of glasses and melts in the Cs2O-B2O3-SiO2 system in the framework of the generalized lattice theory of associated solutions

Abstract

The possibility of calculating the thermodynamic properties of glasses and melts in the Cs 2 O-B 2 O 3 -SiO 2 system formed by two glass-former oxides and one modifier oxide with the use of the vacancy variant of the generalized lattice theory of associated solutions is demonstrated. A comparison with the experimental thermodynamic functions determined earlier by high-temperature differential mass spectrometry and electromotive force method shows that the calculations performed within this approach lead to reliable thermodynamic functions. The thermodynamic properties and structural features (the relative numbers of bonds with due regard for the second coordination sphere) of glasses and melts in the Cs 2 O-B 2 O 3 -SiO 2 system are analyzed in terms of the generalized lattice theory of associated solutions.

Simulation of the thermodynamic properties of glass-forming melts in the Na2O-B2O3-SiO2 system in the framework of the generalized lattice theory of associated solutions

“…As in our earlier work [17] devoted to the description of the thermodynamic properties of glasses and melts in the Cs 2 O-B 2 O 3 -SiO 2 system, the model parameters used for calculating the thermodynamic properties of melts in the Na 2 O-B 2 O 3 -SiO 2 system were chosen as follows: Q Na-O-= 1 is the number of [Na 2 O] 1/2 contact points corresponding to Na-O-[…] bonds with due regard for the second coordination sphere; Q Na-o-= 2 is the number of [Na 2 [16], and Cs 2 O-B 2 O 3 -SiO 2 [17] systems, were taken to be vacant. This value was chosen because the sodium ion is singly charged and the [Na 2 O] 1/2 structural unit has three contact points.…”

“…Taking into account the basic concepts of the generalized lattice theory of associated solutions [3][4][5] and the vacancy variant of this approach [14,17] and also the properties of individual oxides forming melts in the Na 2 O-B 2 O 3 -SiO 2 system, the equations for describing the thermodynamic properties of this system can be represented in the form (1) …”

“…As was shown in our previous work [17], according to the basic concepts of the generalized lattice theory of associated solutions [3][4][5], the relative numbers of bonds that can be formed with the highest probability in the glass or melt were determined from the expressions…”

“…In our previous work [17], the thermodynamic properties of glasses and melts in the Cs 2 O-B 2 O 3 -SiO 2 system were calculated within the vacancy variant of the generalized lattice theory of associated solutions. It was demonstrated that the calculated values of the activities of the components and the integral Gibbs energies are in reasonable agreement with the experimental data and the error in the calculation does not exceed 21%.…”

High Temperature Mass Spectrometric Study of Thermodynamic Properties and Vaporization Processes of Oxide Systems: Experiment and Modeling

“…The generalized lattice theory of associated solutions was successfully applied earlier for the calculation of thermodynamic properties of B 2 O 3 -GeO 2 [9,58,59] systems. The relative numbers of various types of bonds formed in these melts when the second coordination spheres were taken into consideration as a function of composition were calculated based on GLTAS.…”