Synthesis, characterization and heat capacities of ternary oxides in the Ti–Nb–O system

• Synthesis, characterization and heat capacities of TiNb2O7, Ti2Nb10O29 and TiNb24O62.
• Heat capacity by differential scanning calorimetry.
• Smoothed heat capacities data for temperature range 0–850 K using Debye and Einstein functions.
• Thermodynamic data tables for all three oxides.

Three different ternary oxides TiNb2O7, Ti2Nb10O29 and TiNb24O62 were prepared by solid-state reaction route and characterized by X-ray powder diffraction method. The standard molar heat capacities of these oxides were measured in the temperature range 125–850 K using differential scanning calorimetry. Since, the deviation from additive oxide was found to be insignificant, the low temperature values were extrapolated to 0 K using Debye extrapolation method and smoothed heat capacities data for temperature range 0–850 K were generated using a six-term fitting equation based on Debye and Einstein functions. By employing these smoothed heat capacities data the thermodynamic data tables were generated for all three oxides.