Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Heat capacity and thermodynamic properties of lanthanum orthoniobate

Nikiforova, Galina, Khoroshilov, Andrey, Tyurin, Aleksander, Gurevich, Vyacheslav, Gavrichev, Konstantin
J. Chem. Thermodyn. 2019, 132, 44-53
ABSTRACT
Temperature dependences of the heat capacity and the enthalpy change of LaNbO4 were measured using various calorimetric methods (adiabatic, differential scanning and drop calorimetry). It was confirmed that heat capacity has a step-like form in the region of the phase transition, and the second order phase transition "fergusonite-scheelite" proceeds without a thermal effect. Based on the smoothed values of heat capacity, thermodynamic functions (entropy, enthalpy change and Gibbs energy) were calculated over the temperature range from (2-1600) K.
Compounds
# Formula Name
1 LaNbO4 lanthanum orthoniobate
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • Triple point temperature, K ; Crystal 2
  • Crystal 2
  • Crystal 1
  • Air at 1 atmosphere
  • DSC
  • 1
  • POMD
  • 1
  • Mass density, kg/m3 ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • X-ray diffraction
  • 1
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • Small (less than 1 g) adiabatic calorimetry
  • 145
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • DSC
  • 78
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 1
  • Temperature, K; Crystal 1
  • Pressure, kPa; Crystal 1
  • Crystal 1
  • DSC
  • 99
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • DSC
  • 11
  • POMD
  • 1
  • Molar entropy, J/K/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • DSC
  • 11
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • DSC
  • 11
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 1
  • Temperature, K; Crystal 1
  • Pressure, kPa; Crystal 1
  • Crystal 1
  • DSC
  • 10
  • POMD
  • 1
  • Molar entropy, J/K/mol ; Crystal 1
  • Temperature, K; Crystal 1
  • Pressure, kPa; Crystal 1
  • Crystal 1
  • DSC
  • 10
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal 1
  • Temperature, K; Crystal 1
  • Pressure, kPa; Crystal 1
  • Crystal 1
  • DSC
  • 10
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • Small (less than 1 g) adiabatic calorimetry
  • 48
  • POMD
  • 1
  • Molar entropy, J/K/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • Small (less than 1 g) adiabatic calorimetry
  • 48
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal 2
  • Temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • Small (less than 1 g) adiabatic calorimetry
  • 48
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal 2
  • Lower temperature, K; Crystal 2
  • Upper temperature, K; Crystal 2
  • Pressure, kPa; Crystal 2
  • Crystal 2
  • Drop calorimetry
  • 4
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal 1
  • Lower temperature, K; Crystal 1
  • Upper temperature, K; Crystal 1
  • Pressure, kPa; Crystal 1
  • Crystal 1
  • Drop calorimetry
  • 8