title: Observation of a photoexcited state of a paramagnetic transition metal complex by time-resolved electron paramagnetic resonance spectroscopy.
abstract: The first observation of a spin polarized excited state of a paramagnetic metal-complex using time-resolved electron paramagnetic resonance (TREPR) spectroscopy is reported for octaethylporphinatooxovanadium(iv). The TREPR spectra show well resolved orientation dependent hyperfine splitting to the I = 7/2 vanadium nucleus. The reduction of the hyperfine splitting by a factor of 3 compared to the ground state and the observation of a multiplet pattern of spin polarization allow the TREPR spectra to be assigned to the excited quartet state of the complex. The spin polarization patterns evolve with time and it is postulated that this is a result of the equilibration between the lowest excited quartet and doublet states.
authors.affiliation: Department of Chemistry, Brock University, 500 Glenridge Ave., St. Catharines Ont., Canada L2S 3A1.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kandrashkin
authors.forename: Motoko S
authors.initials: MS
authors.lastname: Asano
authors.forename: Art
authors.initials: A
authors.lastname: van der Est
mesh_terms: D004574:Electromagnetic Fields; D004578:Electron Spin Resonance Spectroscopy; D008670:Metals / Q000737:chemistry; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry; D010777:Photochemistry; D011166:Porphyrins / Q000737:chemistry; D014638:Vanadates / Q000737:chemistry
chemical_list: D008670:Metals; D009942:Organometallic Compounds; D011166:Porphyrins; C488938:octaethylporphyrin; C075743:oxovanadium IV; D014638:Vanadates