In this thesis research is presented into multiple unexplained phase transitions of the two antiferromagnets FePS3 and Fe1-xS (pyrrhotite). X-ray diffraction and resistivity measurements of...Show moreIn this thesis research is presented into multiple unexplained phase transitions of the two antiferromagnets FePS3 and Fe1-xS (pyrrhotite). X-ray diffraction and resistivity measurements of pressurised FePS3 show that this material undergoes at least two crystallographic phase transitions, strongly related to the appearance of an exotic metallic state when pressures over approximately 10GPa are applied. Magnetisation, specific heat and resistivity measurements of Pyrrhotite highlight for the first time the dual nature of the Besnus transition. Compelling evidence is presented that excludes the proposition of extrinsic magnetic coupling between differently ordered vacancy superstructures as the underlying mechanism. Instead the presence of local magnetic domain formation is highlighted.Show less
