title: Probing the metal-to-ligand charge transfer first excited state in (η6-naphthalene)Cr(CO)3 and (η6-phenanthrene)Cr(CO)3 by resonance Raman spectroscopy and density functional theory calculations.
abstract: The nature of the lowest energy optical transition for the complexes (η(6)-naphthalene)Cr(CO)(3) and (η(6)-phenanthrene)Cr(CO)(3) in the solid state has been investigated by Raman spectroscopy using a range of different excitation wavelengths progressively approaching the resonant condition. Examination of the resonantly enhanced Raman modes confirms that the first absorption is attributed predominantly to a metal-to-arene charge transfer transition for both complexes. A notable difference in the photochemistry of the two complexes was observed. In the case of the phenanthrene complex, population of the lowest energy excited state leads to a photochemical process which resulted in the loss of the arene ligand and formation of Cr(CO)(6).
authors.affiliation: National Bioimaging Platform of Ireland, and The School of Chemical Sciences, Dublin City University, Dublin, Ireland.
authors.forename: Gennaro
authors.initials: G
authors.lastname: Picardi
authors.forename: Tia E
authors.initials: TE
authors.lastname: Keyes
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Forster
authors.forename: Conor
authors.initials: C
authors.lastname: Long
mesh_terms: D002857:Chromium / Q000737:chemistry*; D008024:Ligands; D008027:Light; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010616:Phenanthrenes / Q000737:chemistry*; D055668:Photochemical Processes / Q000528:radiation effects; D010777:Photochemistry; D011789:Quantum Theory; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity
chemical_list: D008024:Ligands; D009281:Naphthalenes; D009942:Organometallic Compounds; D010616:Phenanthrenes; D002857:Chromium; C031721:naphthalene; C031181:phenanthrene