A theoretical study of the oxygen K absorption edge in cluster models of sodalite

• Published in: Chemical physics Vol. 173; no. 3; pp. 357 - 366
• Main Authors: Zygmunt, S.A., Curtiss, L.A., Iton, L.E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.07.1993; Elsevier
• Subjects: ABSORPTION; Atomic and molecular clusters; Atomic and molecular physics; ATOMS; BACKSCATTERING; CATIONS; CLUSTER MODEL; Exact sciences and technology; K ABSORPTION; NUCLEAR PHYSICS AND RADIATION PHYSICS; OXIDES; OXYGEN; Physics; SILICA; SPECTRA; Studies of special atoms, molecules and their ions; clusters; Molecular structure; Transition metal Compounds; Dipole approximation; Molecular cluster; Theoretical study; Ionization potential; Structural model; Aluminium Sodium Chlorosilicates; Multiple scattering
• ISSN: 0301-0104
• DOI: 10.1016/0301-0104(93)80151-X

The X-ray absorption near-edge spectrum (XANES) has been calculated for the oxygen K-edge in cluster models of pure silica sodalite and a related sodalite containing Al. Results are reported which describe the dependence of the calculated near-edge spectrum on cluster size as well as the presence of Al and the charge-balancing Na cations. Prominent features of the calculated spectra appear to be correlated with the underlying structure of the cluster models. In agreement with other calculations and measurements of near-edge structure in oxides, backscattering of the outgoing photoelectron from 0 atom neighbors is the dominant source of XANES structure, whereas backscattering from Si atoms has a relatively minor effect. Also calculated was the spectrum of a small cluster model of α-SiO 2, which compared favorably with a previously reported experimental near-edge spectrum.