Thermodynamics of oxidic systems of titanium and vanadium at low temperatures

Polycrystalline sample of oxide of Vsub(2)sub(3.004+-0.004)) composition was prepared by V2O5 reduction with hydrogen at approximately 1100 deg C. Specific heat of the sample (39.222 g) was measured by the method of adiabatic calorimetry within 12.1-300.6 K range. Entropy and enthalpy difference values are calculated under standard conditions: Ssub(298.15sup(0)=(94.64+-0.30)J/(molxK), Hsub(298.15sup(0)-Hsub(0)sup(0)=(17150+-60)J/mol, Csub(p, 298.15)sup(0)=(101.0+-0.2)J/(molxK). Phase transition of the first kind, followed by change of conductivity nature in the substance (metal-non-metal transition) was studied. Tsub(trans)=(174+-1)K, ΔSsub(trans)=(10.5+-0.2)J/(molxK), ΔHsub(trans)=(1850+-40)J/mol