Departament Química Física i Analítica, Universitat Jaume I, 12071 Castelló de la Plana, Spain.
Inorg Chem. 2012 Feb 6;51(3):1751-9. doi: 10.1021/ic202056b. Epub 2011 Dec 19.
Theoretical investigations concerning possible calcium sulfate, CaSO(4), high-pressure polymorphs have been carried out. Total-energy calculations and geometry optimizations have been performed by using density functional theory at the B3LYP level for all crystal structures considered. The following sequence of pressure-driven structural transitions has been found: anhydrite, Cmcm (in parentheses the transition pressure) → monazite-type, P2(1)/n (5 GPa) → barite-type, Pnma (8 GPa), and scheelite-type, I4(1)/a (8 GPa). The equation of state of the different polymorphs is determined, while their corresponding vibrational properties have been calculated and compared with previous theoretical results and experimental data.
已对可能的硫酸钙（CaSO(4)）高压多晶型物进行了理论研究。使用密度泛函理论（B3LYP 水平）对所有考虑的晶体结构进行了总能量计算和几何优化。发现了以下压力驱动的结构转变序列：硬石膏，Cmcm（括号中的转变压力）→独居石型，P2(1)/n（5 GPa）→重晶石型，Pnma（8 GPa）和白钨矿型，I4(1)/a（8 GPa）。确定了不同多晶型物的状态方程，同时计算了它们对应的振动特性，并与先前的理论结果和实验数据进行了比较。
