High-Pressure Electrical, Raman, and Structural Measurements on Lithium Sulfide

High-Pressure studies have been conducted on Lithium Sulfide (Li$_{\mathrm{2}}$S) to 55 GPa, with electrical, structural, and Raman measurements. Due to the highly reactive nature of the sample in air, the loading was conducted in a glove bag under an inert Argon atmosphere. Four probe electrical measurements using designer diamond anvils showed characteristic semiconducting behavior in Li$_{\mathrm{2}}$S up to 33GPa from ambient temperature to 10 K. Li$_{\mathrm{2}}$S was compressed to 55GPa and angle dispersive X-Ray data was collected at the Advanced Photon Source, Argonne National Lab, which showed a phase transition from a face centered cubic phase to a primitive orthorhombic phase. Raman data was obtained for Li$_{\mathrm{2}}$S at ambient conditions after decompression from 55 GPa. The Raman Spectrum showed the characteristic peak for Li$_{\mathrm{2}}$S at 372.5 wavenumbers, but had an additional uncharacteristic peak at 327.4 wavenumbers. There is a possibility that the additional uncharacteristic Raman peak is due to the decomposition of Li$_{\mathrm{2}}$S at high pressure.