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Register a new userX-ray Resonant Magnetic Scattering : Polarisation Dependence in the non-spherical case
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Authors
Alessandro Mirone
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We develop a simple tensorial contraction method to obtain analytical formula for X-ray resonant magnetic scattering. We apply the method considering first electric dipole-dipole and electric quadrupole-quadrupole scattering in the isolated atom approximation and compare the results with previous works. Then we apply the method to derive phenomenological original formulas which account also for non-spherical systems and for dipole-quadrupole mixing.
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Simple analytical formulae, directly relating the experimental geometry and sample orientation to the measured R(M)XS scattered intensity are very useful to design experiments and analyse data. Such formulae can be obtained by the contraction of an expression containing the polarisations and crystal field tensors, and where the magnetisation vector acts as a rotation derivativecite{mirone}. The result of a contraction contains a scalar product of (rotated) polarisation vectors and the crystal field axis. The contraction rules give rise to combinatorial algorithms which can be efficiently treated by computers. In this work we provide and discuss a concise Mathematica code along with a few example applications to non-centrosymmetric magnetic systems.
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