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

The compressibility, compression mechanism, and electronic properties of berndtite, SnS₂, have been investigated by angular-dispersive X-ray powder diffraction experiments and ab initio calculations up to 10 GPa. The compression behaviour of the layered structure is highly anisotropic. The compressibility perpendicular to the layers is one order of magnitude larger than within the layers. The main compression mechanism is the reduction of the van-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 transition of the semiconducting material to a semimetal at still higher pressures probable.