A high pressure x-ray diffraction study of titanium disulfide

Abstract

A high pressure angle dispersive synchrotron x-ray diffraction study of titanium disulfide(TiS2)was carried out to pressures of 45.5 GPa in a diamond-anvil cell. We observed a phase transformationof TiS2 beginning at about 20.7 GPa. The structure of the high pressure phaseneeds further identification. By fitting the pressure–volume data to thethird-order Birch–Murnaghan equation of state, the bulk modulus,K0T, was determinedto be 45.9 ± 0.7 GPa with itspressure derivative, K′0T, being 9.5 ± 0.3 at pressures lower than 17.8 GPa. It was found that the compression behavior ofTiS2 is anisotropic along the different axes. The compression ratio of thec-axis is about ninetimes larger than the a-axis when pressures are lower than 1 GPa. It suddenly decreases to three times larger atpressures of about 3 GPa. This ratio shows a linear decrease with a slope of negative 0.048at pressures below phase transformation.