We investigated the high-pressure phases of sulfur using first-principles calculations with high precision. In a previous study, Rudin et al. [Phys. Rev. Lett. 83, 3049 (1999)] predicted that the β-Po type rhombohedral structure is followed by a simple cubic (sc) structure. Strictly limiting the comparison to the work of Rudin et al. and four atoms per unit cell, our high-precision calculations that couple an originally developed structure search method demonstrate that the proposed sc structure is not the ground state at any pressure value, and that compressed S undergoes a first-order phase transition to a body-centered-cubic phase above 500 GPa. The potential energy surface constructed by the pseudopotential employed by Rudin et al. does not conform with that constructed by an all-electron calculation. Our findings extensively contribute to the ongoing effort in forming an accurate picture of the structural phase transitions of compressed S, and also brings to light the importance of careful treatments necessary when calculating high-pressure states using the pseudopotential method.

中文翻译：

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基于可靠的第一性原理计算的压缩硫研究

我们使用高精度的第一性原理计算研究了硫的高压相。在之前的一项研究中，Rudin等人。[物理。牧师莱特。 [83 , 3049 (1999)] 预测β- Po 型菱面体结构后面是简单的立方(sc) 结构。严格限制与 Rudin等人的工作进行比较。和每个晶胞四个原子，我们结合最初开发的结构搜索方法的高精度计算表明，所提出的 sc 结构在任何压力值下都不是基态，并且压缩的 S 经历一阶相变到体500 GPa 以上的中心立方相。由 Rudin等人使用的赝势构建的势能面。不符合由全电子计算构建的。我们的发现广泛地有助于形成压缩 S 结构相变的准确图像的持续努力，并且还揭示了在使用赝势方法计算高压状态时必要的仔细处理的重要性。