Garnet-perovskite transformation in CaGeO3: In-situ X-ray measurements using synchrotron radiation
Garnet-perovskite transformation in CaGeO3: In-situ X-ray measurements using synchrotron radiation
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CaGeO3 中的石榴石-钙钛矿转变：使用同步加速器辐射进行原位 X 射线测量
DOI：
10.1029/gl012i010p00729
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发表时间：
1985
影响因子：
5.2
通讯作者：
O. Shimomura
中科院分区：
文献类型：
--
作者：
J. Susaki;M. Akaogi;S. Akimoto;O. Shimomura
利用同步辐射技术，在6.5GPa和1200°C的压力-温度范围内研究了CaGeO 3中石榴石-钙钛矿相变。能量色散X射线衍射系统的原位测量使我们能够进行动态观察的转变。石榴石相和钙钛矿相之间的平衡相界被确定为P（GPa）= 6.9 - 0.0008T（°C）。在本研究中明确确定的负P-T斜率与根据热化学数据计算的转变焓值-0.0023（8）GPa/°C相当一致。在约6 GPa和1000°C下，伴随这种转变的摩尔体积变化估计为约13%。
The garnet-perovskite phase transformation in CaGeO3 was investigated in the pressure-temperature region to 6.5 GPa and 1200°C using a cubic anvil type of high-pressure apparatus combined with synchrotron radiation. In-situ measurements with an energy dispersive x-ray diffraction system enable us to carry out dynamical observation of the transformation. The equilibrium phase boundary between the garnet and perovskite phases was determined as P(GPa)= 6.9 - 0.0008T(°C). The negative P-T slope definitely established in the present study is in reasonable agreement with the value, −0.0023(8) GPa/°C, that was calculated from the thermochemical data on the enthalpy of transition. The molar volume change accompanied with this transformation was estimated to be about 13% at about 6 GPa and 1000°C.