Multiple-scattering resonances and structural effects in the x-ray-absorption near-edge spectra of Fe II and Fe III hexacyanide complexes

• DOI: 10.1103/physrevb.26.6502
• Publication Date: 2002-07-26T23:14:26Z
• Authors: A. Bianconi; M. Dell'Ariccia; P. J. Durham; J. B. Pendry
• Keywords: XANES; K-edge

The x-ray-absorption near-edge structure (XANES) at the Fe$K$ edge of ${\mathrm{K}}_{3}$Fe${(\mathrm{CN})}_{6}$ and ${\mathrm{K}}_{4}$Fe${(\mathrm{CN})}_{6}$ has been measured interpreted by means multiple-scattering calculations. theory is able to account for XANES over a 40-eV energy range. We demonstrate that quasidiatomic "shape resonances" arising from multiple scattering within CN groups play an important role in suggest this may be common feature metal atoms bound molecular (e.g., CO, CN,...) containing bonds. effects on bond-length changes distortions coordination geometry Fe${(\mathrm{CN})}_{6}$ cluster have estimated. different spectra ${[\mathrm{F}\mathrm{e}{(\mathrm{CN})}_{6}]}^{2+}$ ${[\mathrm{F}\mathrm{e}{(\mathrm{CN})}_{6}]}^{3+}$ terms charge-induced structural modifications. Comparison with extended fine-structure (EXAFS) diffraction data shows can used as quantitative probe local which are not detected EXAFS.