Suppression of magnetism under pressure in FeS: a LDA+DMFT study

Abstract

We show that evolution of magnetic properties in FeS under pressure cannot be explained only in terms of a spin state transition. While uniform compression does show substantial suppression of the local magnetic moment and increase of the weights of configurations with low spin, analysis of the local spin-spin correlation function demonstrates increase of the spin itinerancy. This is related to a strong modification of the electronic structure under pressure: in the high-pressure phase FeS is in the Fermi-liquid state, while decrease of the pressure moves the system to an orbital-selective regime.