On the effect of short-range magnetic ordering on electron energy-loss spectra in spinels
نویسنده
چکیده
The energy-loss near-edge structure (ELNES) at the oxygen K edge in two AB2O4 spinels (A=Mg, B=Al,Cr) is reported. In MgAl2O4 the experimental data is successfully modelled within the LDA framework. In the case of MgCr2O4 spin-polarisation, in the form of antiferromagnetic ordering on the Cr sub-lattice, must be included despite the fact that the measurements were performed at approximately 30 times above TN . A model in which dynamic short-range antiferromagnetic ordering is present at room temperature is proposed to explain the results of the experiments
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تاریخ انتشار 2004