The importance of multiple scattering pathways involving the absorbing atom in the interpretation and analysis of metal K-edge XAFS data of co-ordination compounds

摘要

The presence of peaks at twice the metal-ligand distance (2R) in the Fourier transform of the Ni K-edge XAFS data of trans-[NiBr_2(PEt_3)_2], and the absence of such peaks in the data of tetrahedral-[NiBr_2(PPh_3)_2] confirm unambiguously that these 2R features are due to multiple scattering pathways involving the central metal atom in linear (or near linear) L-M-L units. Attention is drawn to the dangers of mis-interpreting these 2R features as due to solvation shells or lattice packing.