The correlation of the auger parameter with refractive index: An XPS study of silicates using Zr Lα radiation

Abstract

The value of using Z r L a x-rays as a source tor the XPS study of AI-Si compounds is proved by their ability to generate strong Al and Si 1s and KLL Auger peaks and with sufficient resolution for peak energies to be determined accurately. A study of the resultant A1 and Si Auger parameters has been made for some 30 silicates and comparison with refractive index data allows the Auger parameters to be scaled directly with the polarization energy of the surrounding 0 ions. The 0 polarizability dominates the bulk polarizability in silicates and its magnitude is controlled by its site co-ordination number and the electronegativity of charge-balancing cations in the structure. Oxygen ions surrounding Si and tetrahedral Al sites have highly variable, but strongly interdependent, polarizabilities; however, the 0 polarizability is almost invariant around octahedral A1 sites. The correlation of relaxation energy in a silicate lattice with polarizability is finally compared with the London force interaction between molecules.

High‐energy monochromated Cu Kα1 x‐ray source for electron spectroscopy of materials: initial results

“…Nevertheless a significant body of work has been built up using higher energy x-ray sources, e.g. Si K˛ h D 1739.4 eV , 1 Zr L˛ h D 2042.4 eV , 2 Au M˛ h D 2122.9 eV , 3 Ag L˛ h D 2984.3 eV , 4 Ti K˛ h D 4510.9 eV , 5 Cr Kˇ h D 5946.7 eV , 6 synchrotron sources (up to h D 7 keV) 6 -9 and unmonochromated Cu K˛1 h D 8047.8 eV . 10 Detailed studies of Auger electron emission also have been carried out using high-energy xray sources.…”

Dielectric constant of ultrathinSiO2film estimated from the Auger parameter

“…A shift in the modified Auger parameter is twice the shift in the relaxation energy associated with a core-hole for the atom, 8-10 hence reflecting a change in the of the material. [11][12][13] …”

Silicon K-edge XANES spectra of silicate minerals

“…With the exception of the SiO2 polymorphs, the tectosilicates contain A1 substituting for Si. The structure and bonding of silicates and aluminosilicates have been studied using x-ray photoelectron spectroscopy (XPS) (Adams et al 1972;Urch and Murphy 1974;Adams et al 1977;Wagner et al 1981Wagner et al , 1982West and Castle 1982;Seyama and Soma 1985, t987;Nefedov et al 1988), Auger electron spectroscopy (AES) (Wagner et al 1981(Wagner et al , 1982West and Castle 1982;Nefedov et al 1988), x-ray emission spectroscopy (XES) (Brytov et al 1979; Pitault et al 1981; Wiech and Kurmaev 1985;Pur-Correspondence to: G.M. Bancroft ton and Urch 1989;Urch 1989), x-ray photoelectron diffraction (XPD) (Evans et al 1979;Evans and Raftery 1980), x-ray absorption spectroscopy (XAS) (Brytov and Romashchenko 1978;Brytov et al 1979), magic-anglespinning (MAS) nuclear magnetic resonance (NMR) spectroscopy (for example, Lippmaa et al 1980;Grimmer et al 1981;Smith et al 1983;Klinowski 1984;M/igi et al 1984;Kinsey et al 1985;Weiss et al 1987;Kirkpatrick 1988;Sherriff and Grundy 1988;Sherriff et al 1991), and molecular orbital (MO) calculation (Tossell 1973(Tossell , 1975Tossell and Gibbs 1977;…”