TY - JOUR
T1 - Energetics of the oxygen vacancy order-disorder transition in Ba2ln2O5
AU - Prasanna, T. R.S.
AU - Navrotsky, Alexandra
N1 - Funding Information:
We thank Dr. L. Topor for helpful discussions and Dr. E. A. Smelik for help in drawing Fig. 1. This work was supported by the National Science Foundation (Grant DMR 89-12549).
PY - 1993/7
Y1 - 1993/7
N2 - The heat capacity and the enthalpy associated with the reported oxygen vacancy order-disorder transition in Ba2In2O5were measured by high temperature step scanning calorimetry. The transition temperature is 1205 ± 2 K. The transition appears first order or nearly so. The enthalpy and entropy of transition are 1.3 kJ/mol and 1.1 J/mol K, respectively. The latter is only 4.8% of the configurational entropy, arising from mixing one vacancy and five oxygens per formula unit, 22.5 J/mol K. This suggests that the transition involves only a small fraction of the oxygen vacancies and implies extensive short-range order, SRO, in the high temperature phase.
AB - The heat capacity and the enthalpy associated with the reported oxygen vacancy order-disorder transition in Ba2In2O5were measured by high temperature step scanning calorimetry. The transition temperature is 1205 ± 2 K. The transition appears first order or nearly so. The enthalpy and entropy of transition are 1.3 kJ/mol and 1.1 J/mol K, respectively. The latter is only 4.8% of the configurational entropy, arising from mixing one vacancy and five oxygens per formula unit, 22.5 J/mol K. This suggests that the transition involves only a small fraction of the oxygen vacancies and implies extensive short-range order, SRO, in the high temperature phase.
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U2 - 10.1557/JMR.1993.1484
DO - 10.1557/JMR.1993.1484
M3 - Article
AN - SCOPUS:0027625158
SN - 0884-2914
VL - 8
SP - 1484
EP - 1486
JO - Journal of Materials Research
JF - Journal of Materials Research
IS - 7
ER -