ABSTRACT Raman spectroscopy was performed on some metallosilanes, chelat-substituted tetracarbonyl complexes, and trans-[CpFe(CO)2]2 (Cp = η5-C5H5). The vibrational spectra of different silyl complexes are discussed by means of normal coordinate calculations for the M-SiH3 fragment. The calculated force fields and potential energy distributions demonstrate the complicated vibrational behaviour of the metallosilanes as well as the influence of the remaining ligands. A complete normal coordinate analysis (NCA) was carried out for Cp(CO)2Fe-SiH3, including the whole Cp ligand. Matrix isolation Raman spectroscopy was used to study the photochemistry of carbonyl metal silyl complexes. Results of the irradiation experiments of Cp(CO)2Fe-SiH2(CH3) at 20 K isolated in a krypton matrix are discussed. High resolution low-temperature Raman spectra of polycrystalline cis-(L-L)M(CO)4 complexes show characteristic v(CO) splitting patterns interpreted by crystal effects. Results are presented from factor group analyses of (dppm)Mo(CO)4 [dppm = bis(diphenylphosphino)methane] and (dppe)Cr(CO)4 [dppe = bis(diphenylphosphino)ethane]. Resonance Raman studies of polycrystalline and matrix isolated trans-[CpFe(CO)2]2 leads to an assignment of the characteristic modes and the detection of a triply bridged Cp2Fe2(CO)3 photogenerated intermediate.
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