Magnetism and the Verwey transition in Fe3O4 under pressure

We have used high precision neutron diffraction and ab initio calculations to investigate the behavior of the magnetism of spinel magnetite (Fe3O4) under pressure in the 0-10 GPa range and at temperatures of 130-300 K. We find a significant but continuous decrease of the magnetic moments at both the A and B sites to at least 10 GPa, as well as an absence of any detectable pressure dependence of the oxygen atomic parameter. The data indicate a very weak dependence of the saturation moment on pressure and temperature and rule out unambiguously a transition from inverse to normal spinel in the P/T range investigated. Consequently, charge ordering cannot be precluded as the origin of the Verwey transition under pressure.