Oxygen-metal bonding in Ti-bearing compounds from O 1s spectra and ab initio full multiple-scattering calculations

The O K-edge spectra of a series of Ti-bearing compounds with Ti in different structural and chemical environments have been measured using electron energy-loss spectroscopy and analyzed using ab initio full multiple-scattering (MS) calculations. The near-edge structures arise mainly from covalency by direct and/or indirect interaction between O and metal atoms and between O and Si atoms. The coordination number of the cation and the site symmetry also influence the spectral shape and structures. Using different size clusters around the excited atom in the full MS simulation, it is possible to interpret and assign the features present in the spectra of each compound to its specific atomic arrangement and electronic structure. Keywords: oxygen-metal bonding; Ti-bearing compounds; electron energy-loss spectroscopy; ab initio full multiple-scattering calculations; coordination numbers; site symmetry.