Eur. Phys. J. Special Topics 208, 21-38 (2012)
https://doi.org/10.1140/epjst/e2012-01604-5

Review

Resonant X-ray diffraction: Basic theoretical principles

¹ Institut Néel, CNRS and Université Joseph Fourier, BP. 166, 38042 Grenoble Cedex 9, France
² Équipe de Physique des Surfaces et Interfaces, Institut de Physique de Rennes, CNRS UMR 6251, Université de Rennes 1, Rennes, France
³ IMPMC, CNRS UMR 7590, Université Pierre et Marie Curie Paris VI, IPGP, 4 place Jussieu, 75052 Paris Cedex 05, France

^a e-mail: yves.joly@grenoble.cnrs.fr

Received: 7 January 2012
Revised: 23 March 2012
Published online: 15 June 2012

Abstract

We present the main steps governing the theory of resonant X-ray diffraction (RXD). We focus on the derivation of the anomalous scattering amplitude from perturbation theory and starting from the low-energy expansion of the Dirac Hamiltonian. We give the main ingredients of the multipolar expansion in term of electric and magnetic transitions. We also show the expansion in terms of scattering tensors of the material. We end by giving the RXD formula necessary to simulate in practice this spectroscopy.