|
|||||
|
|
Relativistic multiple scattering theory of K-edge X-ray magnetic circular dichroism |
|
| Affiliation: | 1. Advanced Centre for Research in High Energy Materials (ACRHEM), University of Hyderabad, Hyderabad 500046, India;2. Inter-University Accelerator Centre, New Delhi 110067, India;1. Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, Suzhou Research Institute of Southeast University, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, PR China;2. Jingjiang People’s Hospital, Jingjiang 214504, PR China;1. CNR—Istituto Officina dei Materiali (IOM), Laboratorio TASC, 34149 Trieste, Italy;2. CNR—Istituto di Struttura della Materia (ISM), Basovizza Area Science Park, 34149 Trieste, Italy;3. CNR—Istituto di Fotonica e Nanotecnologie (IFN), via Trasea 7, 35131 Padova, Italy;4. MAX IV Laboratory, Lund University, P.O. Box 118, 22100 Lund, Sweden;5. Elettra-Sincrotrone Trieste, Area Science Park Basovizza, 34149 Trieste, Italy |
| Abstract: | We discuss the angular dependent K-edge X-ray magnetic circular dichroism (XMCD) spectra based on the non-relativistic Green’s function expansion of the relativistic 4×4 Green’s function developed by Gesztesy et al. [Ann. Inst. Henri Poincaré 40 (1984) 159]. For the core functions we use the Dirac equation solutions whereas the relativistic effects for photoelectrons are automatically taken into account in the Gesztesy expansion. Analyses of the angular anisotropy provides us useful information on local symmetry violation around X-ray absorbing atoms even though we include relativistic effects. We explicitly show three different types of the symmetry which give rise to the suppression of the sin β-dependence in XMCD spectra. We also present explicit formulas of XMCD for randomly oriented and spatially fixed systems. Discussion on Debye–Waller factors is given in the present theoretical framework. Some illustrative calculations are also shown to understand the relativistic effects on the XMCD. The results are given for the Gd L1-edge and Fe K-edge XMCD. |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ | |