Article
Thermophysical Properties of Materials
2012. V. 50. № 1. P. 56–60
Gusarov A.V., Osina E.L.
Anharmonicity in the V2O3 molecule and thermodynamic properties of V2O3 in the gas phase
Annotation
A quantum-mechanical calculation of the relative stability, structural parameters, and vibrational frequencies of V2O3 molecule isomers for different spin states was carried out using the BPW91/6-311+G(d,p) method. It was shown that the isomer with the Cs structure (nonplanar VOVO rectangle with an O atom attached to it) in the X5A″ electronic state possesses the maximum stability. The energy of the C_{2v} symmetry structure was higher than the lowest energy by just 23 \text{ cm}^{-1}. It definitely indicated the impossibility of usage of the harmonic model in order to calculate the thermodynamic functions of \mathrm{V_2O_3}(g). A model is proposed based on which the energy levels and vibrational sums of states for this type of motion were calculated for the C_s\to C_{2v}\to C_s transition coordinate. These data, as well as results obtained from quantum-mechanical calculations, were used to calculate the thermodynamic functions of \mathrm{V_2O_3}(g) in the temperature range of T=100–6000 K. The calculations were performed with the five excited electronic states with energies from 1000 to 9000\text{ cm}^{-1} taken into account. A comparison with the data calculated in the “rigid rotator-harmonic oscillator” approximation was performed.
Article reference:
Gusarov A.V., Osina E.L. Anharmonicity in the \mathrm{V_2O_3} molecule and thermodynamic properties of \mathrm{V_2O_3} in the gas phase, High Temp., 2012. V. 50. № 1. P. 56
Gusarov A.V., Osina E.L. Anharmonicity in the \mathrm{V_2O_3} molecule and thermodynamic properties of \mathrm{V_2O_3} in the gas phase, High Temp., 2012. V. 50. № 1. P. 56