Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Thermodynamic properties of synthetic turkestanite KNaCaTh(Si8O20)

Knyazev, A. V., Smirnova, N. N., Manyakina, M. E., Shushunov, A. N., Bulanov, E. N., Lelet, M. I., Savushkin, I. A.
J. Chem. Thermodyn. 2016, 92, 8-11
ABSTRACT
In the present work, the temperature dependence of heat capacity of KNaCaTh(Si8O20) has been measured for the first time within the range from T = 6 K to T = 347 K by precision adiabatic vacuum calorimetry. The experimental values were used to calculate standard thermodynamic functions, namely the heat capacity Cp (T), enthalpy Ho(T)-Ho(0), entropy So(T)-So(0) and Gibbs function Go(T)-Ho(0), for the range from T?0 K to 347 K. The value of the fractal dimension D in the function of multifractal generalization of Debye s theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. The incongruent melting point of KNaCaTh(Si8O20) was determined by differential scanning calorimetry.
Compounds
# Formula Name
1 CaKNaO20Si8Th calcium potassium sodium thorium(4+) silicate [KNaCaTh(Si8O20)]
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
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Vacuum adiabatic calorimetry
  • 42
  • POMD
  • 1
  • Molar enthalpy, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Vacuum adiabatic calorimetry
  • 42
  • POMD
  • 1
  • Molar entropy, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Vacuum adiabatic calorimetry
  • 42
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • Vacuum adiabatic calorimetry
  • 166