Normal coordinate analysis of MSiH3 moieties in transition metal complexes and comparison to results obtained for silyl halides

Abstract In order to examine the influence of the transition metal on the metal-silyl fragment MSiH 3 and the metal-silicon bond, polarized Raman spectra of the complexes (C 5 R 5 )(CO) 2 FeSiH 3 R = H (Cp) (1a), Me (Cp ∗ ) (1b)], (C 5 H 5 )(CO)(PPh 3 )FeSiH 3 (1c), (C 5 Me 5 )(CO) 2 RuSiH 3 (2), (C 5 R 5 )(CO) 2 (PMc 3 )MoSiH 3 [R = H (3a), Me (3b)], and (C 5 R 5 )(CO) 2 (PMe 3 )WSiH 3 [R = H(4a), Me (4b)] have been recorded. The spectral data have been evaluated and interpreted on the basis of a normal coordinate analysis of the MSiH 3 core and the derived force constants and potential energy distributions were compared to results obtained for analogous halogen derivatives in the series XSiH 3 [ X = Br (5), I (6)].