title: Infrared spectra of RuTPP, RuCOTPP, and Ru(CO)2TPP isolated in solid argon.
abstract: Infrared spectra of unstable species such as CO-free ruthenium tetraphenylporphyrin RuTPP and RuCOTPP (species with vacant coordination sites) isolated in solid argon at 8 K have been recorded. Selective deposition conditions allow the isolation of either RuTPP and RuCOTPP or RuCOTPP and Ru(CO)2TPP. This depends on the preparation conditions of the sample. A specific Ru-CO bending mode has been characterized at 590.1 cm(-1) for Ru(CO)2TPP. The behavior of each vibrational mode of RuTPP, RuCOTPP, and Ru(CO)2TPP has been analyzed. Modes such as gamma8 at 721.3 cm(-1) (out-of-plane stretching mode gamma(Cbeta-H)sym) and nu41 at 1342.8 cm(-1) (nuCalpha-N coupled with deltaCalpha-Cm) reflect the charge transfer in the porphyrin. Indeed, the addition of one or two CO ligands to RuTPP reduces the charge transfer between the metal center and the porphyrin, which appears as an increase in the frequency of the nu41 mode and in a decrease in that of the gamma8 mode.
authors.affiliation: L.A.D.I.R./U.M.R. 7075 CNRS-Université Pierre et Marie Curie, Boîte 49, 4 Place Jussieu, 75252 Paris, Cedex 05, France. krim@ccr.jussieu.fr
authors.forename: Lahouari
authors.initials: L
authors.lastname: Krim
authors.forename: Sébastien
authors.initials: S
authors.lastname: Sorgues
authors.forename: Benoit
authors.initials: B
authors.lastname: Soep
authors.forename: Niloufar
authors.initials: N
authors.lastname: Shafizadeh
mesh_terms: D001128:Argon; D002248:Carbon Monoxide / Q000302:isolation & purification; D008958:Models, Molecular; D008968:Molecular Conformation; D011166:Porphyrins / Q000737:chemistry* / Q000302:isolation & purification*; D012428:Ruthenium / Q000737:chemistry* / Q000302:isolation & purification*; D013055:Spectrophotometry, Infrared; D013816:Thermodynamics; D014732:Vibration
chemical_list: D011166:Porphyrins; C409084:tetraphenylporphyrin; D001128:Argon; D002248:Carbon Monoxide; D012428:Ruthenium