Single crystal X-ray diffraction study of MgSiO3 perovskite from 77 to 400 K
Single crystal X-ray diffraction study of MgSiO3 perovskite from 77 to 400 K
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DOI：
10.1007/bf00197010
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发表时间：
1989-04
影响因子：
1.4
通讯作者：
N. Ross;R. Hazen
中科院分区：
文献类型：
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作者：
N. Ross;R. Hazen
MgSiO3钙钛矿的单晶X射线衍射研究已完成77~400 K。298~381 K的热膨胀系数为2.2(8)×10-5K-1。在400 K以上，单晶变得多重孪晶，以至于无法再确定电池参数。在77至298 K范围内，MgSiO3钙钛矿的平均热膨胀系数为1.45(9) × 10-5K-1，这与理论模型和钙钛矿系统学一致。热膨胀是各向异性的； a 轴显示在此温度范围内膨胀最大 (αa= 8.4(9) × 10-6K-1)，其次是 c(αc= 5.9(5) × 10-6K-1)，然后是 b，表明在此温度范围内没有显着变化。此外，变形（即[SiO6]八面体的倾斜）随着温度的升高而减小。我们得出的结论是，MgSiO3 钙钛矿随温度变化的行为反映了其在压缩下的行为。
Single crystal X-ray diffraction study of MgSiO3perovskite has been completed from 77 to 400 K. The thermal expansion coefficient between 298 and 381 K is 2.2(8) × 10-5K-1. Above 400 K, the single crystal becomes so multiply twinned that the cell parameters can no longer be determined.From 77 to 298 K, MgSiO3perovskite has an average thermal expansion coefficient of 1.45(9) × 10-5K-1, which is consistent with theoretical models and perovskite systematics. The thermal expansion is anisotropic; the a axis shows the most expansion in this temperature range (αa= 8.4(9) × 10-6K-1) followed by c(αc= 5.9(5) × 10-6K-1) and then by b, which shows no significant change in this temperature range. In addition, the distortion (i.e., the tilting of the [SiO6] octahedra) decreases with increasing temperature. We conclude that the behavior of MgSiO3perovskite with temperature mirrors its behavior under compression.