학술논문
Crystal structure and thermodynamic properties of dipotassium diiron(III) hexatitanium oxide.
Document Type
Article
Source
Subject
*CRYSTAL structure
*THERMODYNAMICS
*TITANIUM oxides
*POTASSIUM compounds
*CALORIMETRY
*THERMAL expansion
*TEMPERATURE effect
*HEAT capacity
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Language
ISSN
1388-6150
Abstract
In the present work, the temperature dependence of heat capacity of dipotassium diiron(III) hexatitanium oxide has been measured for the first time in the range from 10 to 300 K by means of precision adiabatic vacuum calorimetry. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity $$ C_{p}^{ \circ } (T) $$, enthalpy $$ H^{ \circ } (T) - H^{ \circ } (0) $$, entropy $$ S^{ \circ } (T) - S^{ \circ } (0), $$ and Gibbs function $$ G^{ \circ } (T) - H^{ \circ } (0) $$ for the range from T → 0 to 300 K. The structure of KFeTiO is refined by the Rietveld method: space group I4/ m, Z = 1, a = 10.1344(2) Å, c = 2.97567(4) Å, V = 305.618(7) Å. The high-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion. [ABSTRACT FROM AUTHOR]