Magnetic ordering has been shown to have a significant effect on the shape of the oxygen K-edge energy-loss near edge structure (ELNES) in a series of chromite spinels. However, the ELNES of these materials has only been simulated using a rough approximation of antiferromagnetism - the true nature of the magnetic interactions responsible for the detailed oxygen K-edge shape is still unknown. Chromite spinels typically undergo transitions to long range ordered antiferromagnetic (AFM) structures at temperatures below ~15K. Dynamic short range magnetic order (SRO) has been observed at temperatures up to 150K using neutron powder diffraction (NPD). It is not clear whether long range magnetic order, short range magnetic order or paramagnetic effects are responsible for the characteristic oxygen K-edge ELNES observed at room temperature. Here we discuss the possibility of carrying out paramagnetic simulations using the real space multiple scattering program FEFF8.2, and show preliminary results of paramagnetic simulations of the oxygen K-edge ELNES of magnesium chromite.
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