High‐pressure phases of sulfur: Topological analysis and crystal structure prediction
High‐pressure phases of sulfur: Topological analysis and crystal structure prediction
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DOI：
10.1002/pssb.201600857
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发表时间：
2017-07
期刊：
影响因子：
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通讯作者：
P. Gavryushkin;K. Litasov;S. S. Dobrosmislov-S.;Z. Popov
中科院分区：
文献类型：
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作者：
P. Gavryushkin;K. Litasov;S. S. Dobrosmislov-S.;Z. Popov
我们应用密度泛函理论（DFT）和演化结构预测算法来研究硫在100 GPa以上的高压行为。基于DFT计算，我们确定了实验观察到的S-III，S-V和β-Po结构之间的能量关系。S-V被发现是不稳定的，并在优化下转化为S-III。从S-III到β-Po的二阶转换特性在理论上是合理的，计算得出的压力约为250 GPa。β-Po结构在低于250 GPa的三角对称中不稳定，并且自发地转变为与S-III相同的单斜结构。计算得出硫从β-Po到简立方（sc）和从简立方到体心立方（bcc）结构的转变压力分别为333和460 GPa。
We apply density functional theory (DFT) and evolutionary structure prediction algorithms to study the high‐pressure behavior of sulfur above 100 GPa. Based on DFT calculations, we determined the energetic relations between experimentally observed S‐III, S‐V, and β‐Po structures. S‐V is found to be unstable and transforms to S‐III under optimization. The second order character of transformation from S‐III to β‐Po is theoretically justified and calculations yield a pressure of about 250 GPa. β‐Po structure is not stable in trigonal symmetry below 250 GPa and spontaneously transforms into a monoclinic structure identical to S‐III. The calculations yield pressures of 333 and 460 GPa for the transitions from β‐Po to simple cubic (sc) and from simple cubic to body centered cubic (bcc) structures of sulfur, respectively.