Isobaric heat capacity and standard thermodynamic properties of NaLaTiO4 and Na2La2Ti3O10 over the range of (7–670) K

• Published in: Journal of thermal analysis and calorimetry Vol. 131; no. 2; pp. 1107 - 1114
• Main Authors: Sankovich, Anna M., Markin, Alexey V., Smirnova, Natalia N., Bal’makov, Mikhail D., Zvereva, Irina A.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.02.2018; Springer Nature B.V
• Subjects: Adiabatic flow; Analytical Chemistry; Chemistry; Chemistry and Materials Science; Curve fitting; Enthalpy; Heat; Heat measurement; Inorganic Chemistry; Measurement Science and Instrumentation; Physical Chemistry; Polymer Sciences; Specific heat; Thermodynamic properties; Na; Layered perovskite-like oxides; La; Ti; DSC; Heat capacity; Standard thermodynamic functions; NaLaTiO; O; Adiabatic calorimetry
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-017-6685-6

The heat capacities of layered perovskite-like oxides NaLaTiO 4 and Na 2 La 2 Ti 3 O 10 were measured by precision adiabatic vacuum calorimetry over the temperature range of (7–350) K and by differential scanning calorimetry over the temperature range of (350–670) K. The standard thermodynamic functions: molar heat capacity C p,m , enthalpy H ( T ) −  H (9), entropy S ( T ) −  S (9), and Gibbs energy −[ G ( T ) −  G (9)] of the compounds were evaluated from the experimental heat capacity temperature dependences over the range of (9–670) K. The extrapolation of heat capacity down to T  = 0 K is incorrect in this case due to the considerable deviation of experimental points from fitting curves obtained on the basis of Debye’s theory.