Recent developments of anomalous X‐ray scattering for non‐crystalline materials with help of reverse Monte Carlo modeling: The example of GeSe2 glass

Abstract

AbstractAnomalous X‐ray scattering (AXS) experiments on glassy GeSe2 were carried out at energies close to the Ge and Se K absorption edges in order to explore the atomic structure in the short‐ and intermediate‐ranges. The partial structure factors, Sij(Q), and the corresponding partial pair‐distribution functions, gij(r), obtained with help of reverse Monte Carlo (RMC) modeling, are in good agreement with the experimental results from neutron diffraction employing isotopic substitution (NDIS), and with the theoretical data from ab initio molecular dynamics simulation. The prepeak in the total structure factor, S(Q), indicating the existence of intermediate‐range order (IRO), does not only result from Ge–Ge atomic correlations, but also contains Ge–Se correlations. From the atomic configuration obtained from RMC modeling, several structural parameters are discussed, such as partial coordination numbers, connections of the Ge(Se1/2)4 tetrahedra, and bond angle distributions.