title: Bacteriocholorophyll a cation radical in solution and in reaction centers of Rhodopseudomonas sphaeroides. Resonance Raman scattering.
abstract: Resonance Raman spectra of the pi-cation of bacterio-chlorophyll a in solution at 30 K are reported and discussed. Outer (formula: see text) bonds of the pyrroles and the methine bridges are weakened by the ionization, while (formula: see text) and Mg-N bonds remain essentially unaffected. Resonance Raman spectra of reaction centers suggest that the positive charge on P-870+ should be localized on a single bacteriochlorophyll molecule by the lifetime of the scattering process (approximately 10(-13)s).
mesh_terms: D001429:Bacteriochlorophylls / Q000378:metabolism*; D002412:Cations; D002734:Chlorophyll / Q000031:analogs & derivatives*; D012242:Rhodobacter sphaeroides / Q000378:metabolism*; D013059:Spectrum Analysis, Raman
chemical_list: D001429:Bacteriochlorophylls; D002412:Cations; D002734:Chlorophyll