Abstract The stability of Fe-poor dolomite, CaMg0.98Fe0.02(CO3)2, was studied by Raman spectroscopy and single-crystal X-ray diffraction at high pressures (P P 1 ¯ with Z = 8 formula units. The combined experimental and theoretical findings show that at high pressures and low to moderate temperatures Dol-IIIc is formed, while at high pressures and high temperatures Dol-V becomes stable. Assuming that thermodynamic equilibrium is obtained at high-pressure, high-temperature conditions, the current study extends our understanding of the phase stability of Fe-poor dolomite polymorphs at upper and lower mantle conditions.

中文翻译：

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贫铁白云石的高压高温相稳定性及白云石-IIIc和白云石-V的结构

摘要 通过拉曼光谱和高压单晶 X 射线衍射（PP 1 ¯，Z = 8 个分子式单元）研究了贫铁白云石 CaMg0.98Fe0.02(CO3)2 的稳定性。理论发现表明，在高压和中低温下形成Dol-IIIc，而在高压和高温下Dol-V变得稳定。假设在高压、高温条件下获得热力学平衡，目前的研究扩展了我们对上地幔和下地幔条件下贫铁白云岩多晶型物相稳定性的理解。