Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Thermophysical properties of Ca2GeO4 over the temperature range between (6 and 350) K

Shushunov, A. N., Gorshkov, O. N., Smirnova, N. N., Somov, N. V., Chigirinskiy, Y. I.[Yu.I.], Bykov, A. B., Nezhdanov, A. V.
J. Chem. Thermodyn. 2014, 78, 58-68
ABSTRACT
The isobaric heat capacity of monocrystalline Ca2GeO4 (olivine structure) has been measured between T = (6 and 350) K by precision adiabatic vacuum calorimetry for the first time. The experimental results have been used to calculate the standard (po = 0.1 MPa) thermodynamic functions Co p;m/R, DT 6Ho m/RT, DT 6So m/R and Uo m/R = DT 6So m/R DT 6Ho m/RT (where R is the universal gas constant) of Ca2GeO4 (cr) over the range from T = (6 to 350) K. The thermal expansion coefficient (a) of this synthetic mineral has been determined from low-temperature X-ray measurements over the range from T = (100 to 300) K. Isochoric heat capacity Cv,m/R has been calculated using this low-temperature X-ray measurements and available compressibility data. The less thanless thanacousticalgreater thangreater than and less thanless thanopticalgreater thangreater than components of the isochoric heat capacity have been estimated. The less thanless thanopticalgreater thangreater than component of the one are calculated from the vibrational frequencies (m) as measured by Raman spectroscopy with different polarization at room temperature and at 1 bar.
Compounds
# Formula Name
1 Ca2GeO4 calcium germanium oxide (Ca2GeO4)
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
  • Small (less than 1 g) adiabatic calorimetry
  • 531
  • POMD
  • 1
  • Molar volume, m3/mol ; Crystal
  • Temperature, K; Crystal
  • Pressure, kPa; Crystal
  • Crystal
  • X-ray diffraction
  • 10