Science. 1979 Nov 16;206(4420):829-30. doi: 10.1126/science.206.4420.829.
Volume and structural data obtained by shock-wave and diamond-cell techniques demonstrate that calcium oxide transforms from the B1 (sodium chloride type) to the B2 (cesium chloride type) structure at 60 to 70 gigapascals (0.6 to 0.7 megabar) with a volume decrease of 11 percent. The agreement between the shockwave and diamond-cell results independently confirms the ruby-fluorescence pressure scale to about 65 gigapascals. The shock-wave data agree closely with ultrasonic measurements on the B1 phase and also agree satisfactorily with equations of state derived from ab initio calculations. The discovery of this B1-B2 transition is significant in that it allows considerable enrichment of calcium components in the earth's lower mantle, which is consistent with inhomogeneous accretion theories.
冲击波和金刚石细胞技术获得的体积和结构数据表明，氧化钙在 60 到 70 千兆帕斯卡（0.6 到 0.7 兆巴）之间从 B1（氯化钠型）转变为 B2（氯化铯型）结构，体积减少 11%。冲击波和金刚石细胞结果的一致性独立地证实了红宝石荧光压力标度约为 65 千兆帕斯卡。冲击波数据与 B1 相的超声测量非常吻合，也与从头算得出的状态方程吻合得令人满意。这种 B1-B2 转变的发现具有重要意义，因为它允许在地球下地幔中钙成分的大量富集，这与非均匀吸积理论一致。
