Second-order phase transition in a SnS orthorhombic crystal under pressure

作者：Gashimzade F M^*; Guseinova D A; Jahangirli Z A; Mekhtiev B G

来源：Physics of the Solid State, 2015, 57(2): 378-380.

DOI：10.1134/S1063783415020110

The existence of a second-order phase transition in a SnS crystal with an orthorhombic lattice has been demonstrated theoretically. The calculation has been performed in the framework of the density functional theory in the plane-wave basis with the ABINIT software package. It has been found that there is an abrupt change in the bulk modulus of the crystal under hydrostatic pressure near the pressure P = 16 GPa. A continuous variation in the volume of the crystal with increasing pressure indicates the occurrence of a second-order phase transition. It has been shown that this phase transition is associated with the softening of the frequency of the low-frequency totally symmetric interlayer mode. The phase transition is a displacive-type transition, during which the symmetry of the crystal changes from simple orthorhombic to base-centered orthorhombic (P (cmn) (D (2h) (16) )-> C (mcm) (D (2h) (17) )).

• 出版日期2015-2