The heat capacities and enthalpy increments of strontium bismuth niobate SrBi2Nb2O9 (SBN) and strontium bismuth tantalate SrBi2Ta2O9 (SBT) were measured by the relaxation method (2 - 150 K), Calvet-type heat-conduction calorimetry (305 - 570 K) and drop calorimetry (773 - 1373 K). The temperature dependences of non-transition heat capacities in the form Cpm = 324.47 + 0.06371T - 5.0755x106/T 2 J K-1 mol-1 (298 - 1400 K) and Cpm = 320.22 + 0.06451T - 4.7001x106/T 2 J K-1mol-1 (298 - 1400 K) were derived for SBN and SBT, respectively, by the least-squares method from the experimental data. Furthermore, the standard molar entropies at 298.15 K Sdeg m(SBN) = 327.15 +- 0.80 J K-1 mol-1 and Sdeg m(SBT) = 339.23 +- 0.72 J K-1 mol-1 were evaluated from the low temperature heat capacity measurements.
Compounds
#
Formula
Name
1
Bi2Nb2O9Sr
bismuth niobium strontium oxide (Bi2Nb2SrO9)
2
Bi2O9SrTa2
strontium bismuth tantalate
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
Large sample (1 g) DSC
38
POMD
1
Molar heat capacity at constant pressure, J/K/mol ; Crystal
Temperature, K; Crystal
Pressure, kPa; Crystal
Crystal
AC calorimetry
95
POMD
1
Molar enthalpy, kJ/mol ; Crystal
Temperature, K; Crystal
Pressure, kPa; Crystal
Crystal
Drop calorimetry
28
POMD
2
Molar heat capacity at constant pressure, J/K/mol ; Crystal
Temperature, K; Crystal
Pressure, kPa; Crystal
Crystal
AC calorimetry
94
POMD
2
Molar heat capacity at constant pressure, J/K/mol ; Crystal