title: Infrared photodissociation spectroscopy of mononuclear iron carbonyl anions.
abstract: The infrared photodissociation spectroscopy of mass-selected mononuclear iron carbonyl anions Fe(CO)(n)(-) (n = 2-8) were studied in the carbonyl stretching frequency region. The FeCO(-) anion does not fragment when excited with infrared light. Only a single IR active band was observed for the Fe(CO)(2)(-) and Fe(CO)(3)(-) anions, consistent with theoretical predictions that these complexes have linear D(∞h) and planar D(3h) symmetry, respectively. The Fe(CO)(4)(-) anion is the most intense peak in the mass spectra and was characterized to have a completed coordination sphere with high stability. Anion clusters larger than n = 4 were determined to involve a Fe(CO)(4)(-) core anion that is progressively solvated by external CO molecules. Three CO stretching vibrational fundamentals were observed for the Fe(CO)(4)(-) core anion, indicating that the Fe(CO)(4)(-) anion has a C(3v) structure. All the carbonyl stretching frequencies of the Fe(CO)(n)(-) anion complexes are red-shifted with respect to those of the corresponding neutrals.
authors.affiliation: Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
authors.forename: Guanjun
authors.initials: G
authors.lastname: Wang
authors.forename: Chaoxian
authors.initials: C
authors.lastname: Chi
authors.forename: Jieming
authors.initials: J
authors.lastname: Cui
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Xing
authors.forename: Mingfei
authors.initials: M
authors.lastname: Zhou