ʹAtomicʹ X-ray absorption fine structure: a new tool for examining electronic and ionic polarization effects

The Zn K-edge X-ray absorption fine structure (XAFS) of Zn(OH)42− ions in basic solution are analyzed. Atomic XAFS (AXAFS) arises from photoelectron scattering off electrons in bonds on the periphery of the absorber. Interactions of the zincate ion with hydrated cations (H2O)nM+ (M=Li+, Na+, K+, and Rb+) are shown to produce significant changes in the AXAFS intensity that result from polarization of the zincate anion by the cation. Both the `through space fieldʹ and `through bond inductiveʹ polarization mechanisms are considered; with the inductive mechanism found to dominate in this case.