In:
Journal of Synchrotron Radiation, International Union of Crystallography (IUCr), Vol. 8, No. 2 ( 2001-03-01), p. 215-217
Abstract:
The preedge features in a system with `even' symmetry, apart from quadrupolar transition contribution, are mainly dipolar in character, associated with the existence of unoccupied states made up of mixed cation-4p with higher-neighboring cation-3d orbitals, and reflect the density of states due to the medium-range order of the system. In `odd' symmetry materials these preedge features are the result of a transition from the 1s to a final density of states of p symmetry due to an unsymmetrical mixing of the ligand wave functions with the central cation 3d orbitals, similar to atetrahedral configuration. These results are validated for Fe as a photoabsorber by comparing XAS spectra of Fe 2 SiO 4 (fayalite) to ab initio full multiple scattering calculations at the Fe K edge, but pertain to all systems containing sixfold-coordinated cations.
Type of Medium:
Online Resource
ISSN:
0909-0495
DOI:
10.1107/S0909049500016502
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
2001
detail.hit.zdb_id:
2021413-3
SSG:
13
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