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Chemical Physics 189 (1994) 757-768

Inner-shell spectroscopy of compounds containing Si-Si bonds: is there a localised, low-energy Si-Si resonance? S.G. Urquhart^a, J.Z. Xiong^b, A.T. Wen^a,1, T.K. Sham^b, K.M. Baines^b, G.G.B. de Souza^c, A.P. Hitchcock^a ^aDepartment of Chemistry, McMaster University, Hamilion, Ontario, Canada L8S 4MI ^bDepartment of Chemistry, University of Western Ontario, London, Ontario, Canada ^cInstituto de Quimica, UFRJ, Rio de Janeiro, RJ, Brazil 21910-900 Received 10 August 1994

ABSTRACT

Oscillator strengths for the Si 2p, Si 2s. and C ls excitation of tetramethylsilane, hexamethyldisilane, tetrakis(trimethylsilyl)silane, and dodecamethylcyclohexasilane have been derived from electron energy loss spectra recorded in the dipole-regime. These results are compared to the Si ls and Si 2p photoabsorption spectra of tetramethylsilane, hexamethyldisilane, tris(trimethylsilyl)silane, and tetrakis(trimethylsilyl)silane, recorded using synchrotron radiation. The spectra support the existence of a localised, low-lying state of large Si-Si character in species which contain Si-Si bonds.