Thermodynamic parameters of scandium trifluoride and triiodide in the condensed state

• Published in: Russian Journal of Physical Chemistry A 2015-06, Vol.89 (6), p.947-951
• Main Authors: Aristova, N. M., Belov, G. V.
• Format: Article
• Language: English
• Subjects: Chemical Thermodynamics and Thermochemistry; Chemistry; Chemistry and Materials Science; Physical Chemistry
• ISSN: 0036-0244; 1531-863X
• DOI: 10.1134/S0036024415060035

The thermodynamic properties of new classes of compounds, particularly scandium trihalides ScF 3 , ScCl 3 , ScBr 3 , and ScI 3 , are added to the IVTANTHERMO software package. A critical analysis and processing of the entire array of primary data available in the literature is performed. An equation approximating the temperature dependence of heat capacity in the temperature range 298.15- T m (K) is derived for each crystalline scandium trihalide. The resulting equations C p po ( T ) for the solid state and the data for the liquid phase are used to calculate the thermodynamic functions of entropy, the reduced Gibbs free energies, and the enthalpy increments. Both the experimental data available in literature and the missing estimated thermodynamic data are used in calculations. The error of the recommended values is estimated in all cases. In the first part of this work, we describe the thermodynamic properties of ScF 3 and ScI 3 used as the reference data for calculating the thermodynamic functions of ScCl 3 and ScBr 3 , for which experimental data are either very scarce or missing altogether. The resulting data are added to the database of the IVTANTHERMO software package.