Formation enthalpies and heat capacities of rear earth titanates: RE2TiO5 (RE=La, Nd and Gd)

被引：32
作者：
Hayun, Shmuel
Navrotsky, Alexandra [1 ]
机构：
[1] Univ Calif Davis, Peter A Rock Thermochem Lab, Davis, CA 95616 USA
来源：
JOURNAL OF SOLID STATE CHEMISTRY | 2012年 / 187卷
基金：
美国国家科学基金会;
关键词：
Rear earth titanates; Formation enthalpy; Heat capacity; PYROCHLORE; IMMOBILIZATION; DIRECTIONS; DISORDER; PROGRESS; WASTE; ORDER;
D O I：
10.1016/j.jssc.2011.12.033
中图分类号：
O61 [无机化学];
学科分类号：
070301 ; 081704 ;
摘要：
The formation enthalpies and heat capacities of orthorhombic rare earth titanates, RE2TiO5 (RE = La, Nd and Gd), have been studied by high temperature differential scanning calorimetry (300-1473 K) and oxide-melt solution calorimetry. The RE2TiO5 samples are stable in enthalpy with respect to their oxides and the pyrochlore RE2Ti2O7 phase. The general trend that has been demonstrated in other RE-ternary systems; decreasing thermodynamic stability with decreasing R-A/R-B was found to be valid for the RE2TiO5, and their enthalpies of formation from oxides become more negative with increasing RE3+ ionic radius. (C) 2012 Elsevier Inc. All rights reserved.
引用
收藏
页码：70 / 74
页数：5
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