Thermodynamics Research Center / ThermoML | Thermochimica Acta

Heat capacity studies of phase transitions in K3Nb3O6(BO3)2

Maczka, M., Wlosewicz, D., Tomaszewski, P. E., Hanuza, J.
Thermochim. Acta 2005, 438, 1-2, 112-115
ABSTRACT
Heat capacity measurements of K3Nb3O6(BO3)2, a borate that exhibits superionic conductivity and ferroelectric properties, have been performed in the 60 220K temperature range. In this work, the presence of two heat capacity anomalies has been documented. The first anomaly occurs at 198.3K and it has been attributed to a first-order phase transition. The second anomaly suggests presence of second-order phase transition at around 80 K.
Compounds
# Formula Name
1 B2K3Nb3O12 niobium potassium borate oxide (Nb3K3(BO3)2O6)
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 enthalpy of transition or fusion, kJ/mol ; Crystal 2
  • Crystal 2
  • Crystal 1
  • Gas
  • ADIACA:FP
  • 1
  • POMD
  • 1
  • Triple point temperature, K ; Crystal 2
  • Crystal 2
  • Crystal 1
  • Gas
  • ADIACA:corrimp
  • 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
  • 182
  • POMD
  • 1
  • Molar heat capacity at constant pressure, J/K/mol ; Crystal 1
  • Temperature, K; Crystal 1
  • Pressure, kPa; Crystal 1
  • Crystal 1
  • Small (less than 1 g) adiabatic calorimetry
  • 44