Amplitudes and phases of electron scattering in polyatomic systems for the structural analysis of disordered, amorphous, and nanosized materials via EXAFS spectroscopy

Resumo

The results from developing and testing a software package for calculating the amplitudes and phases of electron scattering in polyatomic systems are presented. The potential with which an excited electron moves in a medium is constructed using the muffin-tin approximation with Hartree–Fock exchange interaction. Tests of the package for metals, oxides, and iron-bearing water sulphate solutions show that structural parameters can be derived with high degrees of accuracy (the error for interatomic distances is ~0.01 Å; for coordination numbers, it is ~7%). Using the developed approach and software, analysis of the Ag K-EXAFS spectra of silver nanoparticles in silica glass allow us to determine the average structural parameters of Ag–O and Ag–Ag bonds.