RAMAN-SPECTROSCOPIC STUDY OF (PH2P)(2)C=CH2 AND [(PH2P)(2)C=CH2]W(CO)(4)

The Raman and IR spectra of 1,1-bis[diphenylphosphino]ethene (Ph2P)(2) C=CH2 (vdpp) and the tetracarbonyl tungsten complex (vdpp)W(CO)(4) hav e been recorded. Vibrational assignments are proposed based on local s ymmetry considerations. For the vinylidene stretching mode a coordinat ion shift is observed from 1588 cm(-1) in polycrystalline vdpp to 1581 cm(-1) in its tetracarbonyl tungsten complex. From a comparison of th e v(CO) splitting pattern with those of related complexes monoclinic s tructure with factor group C-2h and four formula units per unit cell i s concluded. (C) 1997 Elsevier Science B.V.