A low-temperature structural phase transition in β-MoTe₂

Abstract

Abstract High-precision X-ray measurements on crystals of the layered dichalcogenide β-MoTe2 have revealed a structural transition at approximately 250 K. The transition from the monoclinic room-temperature form is accompanied by a discontinuous change of the monoclinic angle β from 93°55′ to 90°, with substantial thermal hysteresis and coexistence of high- and low-temperature phases. The low-temperature structure is the result of a shear deformation of the layers perpendicular to the c axis.