The high pressure behaviour of SnS2: X-ray powder diffraction and quantum mechanical calculations up to 10 GPa

The compressibility. compression mechanism, and electronic proper ties of b erndtite, SnS2, have been investigated by angular-dispersive X-ray powder d iffraction experiments and ab initio calculations up to 10 GPa. The compres sion behaviour of the layered structure is highly anisotropic. The compress ibility perpendicular to the layers is one order of magnitude larger than w ithin the layers. The main compression mechanism is the reduction of the va n-der-Waals gap as manifested by the decreasing interlayer distance. At 10 GPa the calculations show the onset of a band gap closure. This makes the t ransition of the semiconducting material to a semimetal at still higher pre ssures probable.