ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Specific ion–molecule reactions are used to prepare two intermediates of the FeO++CH4 reaction, and photodissociation of the jet-cooled intermediates is examined in the visible and near-ultraviolet using time-of-flight mass spectrometry. The photodissociation spectrum of the aquo iron carbene complex [H2C(Double Bond)Fe–OH2]+ shows transitions to at least four excited electronic states in the FeCH2+ chromophore, with broad vibrational structure. Photoexcitation of the insertion intermediate [HO–Fe–CH3]+ leads to formation of FeOH++CH3 and also triggers the reaction to produce Fe++CH3OH. The photodissociation spectrum of [HO–Fe–CH3]+ presents a vibrationally resolved band involving progressions in the excited state Fe–C stretch, Fe–O stretch, and O–Fe–C bend. The change in the Fe–C bond length in [HO–Fe–CH3]+ and [H2C(Double Bond)Fe–OH2]+ upon photoexcitation is calculated from a Franck–Condon analysis of the vibronic features observed. The analysis of the experimental results is aided by hybrid Hartree–Fock/density-functional (B3LYP) calculations on [HO–Fe–CH3]+ and [H2C(Double Bond)Fe–OH2]+ performed to determine molecular parameters, and time-dependent density functional theory (TD-DFT) calculations on FeCH2+ to predict excited electronic states. © 2002 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1448489
