Electronic spectroscopy of intermediates involved in the conversion of methane to methanol by FeO¿
نویسندگان
چکیده
chromophore, with broad vibrational structure. Photoexcitation of the insertion intermediate @HO–Fe–CH3# 1 leads to formation of FeOH1CH3 and also triggers the reaction to produce Fe1CH3OH. The photodissociation spectrum of @HO–Fe–CH3# 1 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# 1 and @H2CvFe–OH2# 1 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# 1 and @H2CvFe–OH2# 1 performed to determine molecular parameters, and time-dependent density functional theory ~TD-DFT! calculations on FeCH2 1 to predict excited electronic states. © 2002 American Institute of Physics. @DOI: 10.1063/1.1448489#
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