Thermodynamic properties of single crystals based on lithium tungstate by reaction and DSC calorimetry

For the first time, single crystals of undoped lithium tungstate and lithium tungstate doped by 1.25% molybdenum were grown by the low-temperature-gradient Czochralski technique. The standard formation enthalpies, lattices enthalpies, stabilization energies, and the heat capacity were determined in the temperature range of 320-997 K. The lattice enthalpy dependence on Mo content was constructed.

The low temperature heat capacity of Li2Mo0.05W0.95O4

The heat capacity of a lithium tungstate single crystal doped by 5% molybdenum Li2Mo0.05W0.95O4 in the range of 78.5–302.8 K was measured by the adiabatic method. No anomalous behavior of heat capacity was found. The heat capacity function was obtained in the range of 0–303 K by extrapolating to zero temperature and fitting experimental points. Thermodynamic functions of entropy, enthalpy increment and Gibbs free energy at 298.15 K were calculated using the obtained data.

Heat capacity of lithium tungstate single crystal by DSC calorimetry data in the temperature range of 319-997 K

The heat capacity of lithium tungstate single crystal (Li2WO4) was measured for the first time in the temperature range of 319-997 K. The experiments were carried out by DSC calorimetry. The Li2WO4 single crystal was first grown by low-temperature-gradient Czochralski technique with weight control. The temperature dependence of Li2WO4 heat capacity in the temperature range 319-997 K was monotonic. According to results of our studies, there were no phase transitions in Li2WO4 in the investigated temperature range.