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考查了高压下镁硅酸盐和硅镁氧化物(橄榄石、硅镁尖晶石、钙钛矿及后钙钛矿)中氧、硅的离子半径,发现在压力增加的条件下,不论相变是否发生,氧离子半径总是随压力增加而逐渐缩小的,但对于阳离子硅来说,相变导致它从配位数低的多面体向配位数高的多面体迁移时,其离子半径是逐渐增大的。这种现象与SiO2在高压相变时硅离子增大的趋势完全一致。这种现象可能是在高压下离子化合物逐渐向金属相化合物转变引起的。
The ionic radii of oxygen and silicon in magnesium silicates and silicomagnesium oxides (olivine, magnesia-spinel, perovskite and post-perovskite) under high pressure were examined and it was found that under the conditions of increased pressure, regardless of the phase The change of oxygen ion radius always decreases with the increase of pressure, but for cationic silicon, the phase transition leads to its gradual migration from polyhedron with low coordination number to polyhedron with high coordination number. Increased. This phenomenon is consistent with the tendency of SiO2 to increase during the high-pressure phase transition. This phenomenon may be caused by the transition of ionic compounds to metal phase compounds under high pressure.