title: Two-Dimensional Electronic-Vibrational Spectroscopy of Chlorophyll a and b.
abstract: We present two-dimensional electronic-vibrational (2DEV) spectra of isolated chlorophyll a and b in deuterated ethanol. We excite the Q-band electronic transitions and measure the effects on the carbonyl and C ═ C double-bond stretch region of the infrared spectrum. With the aid of density functional theory calculations, we provide assignments for the major features of the spectrum. We show how the 2DEV spectra can be used to readily distinguish different solvation states of the chlorophyll, with features corresponding to the minority pentacoordinate magnesium (Mg) species being resolved along each dimension of the 2DEV spectra from the dominant hexacoordinate Mg species. These assignments represent a crucial first step toward the application of 2DEV spectroscopy to chlorophyll-containing pigment-protein complexes.
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.|Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.|Kavli Energy Nanoscience Institute at Berkeley , Berkeley, California 94720, United States.
authors.forename: Nicholas H C
authors.initials: NH
authors.lastname: Lewis
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.|Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.|Kavli Energy Nanoscience Institute at Berkeley , Berkeley, California 94720, United States.
authors.forename: Graham R
authors.initials: GR
authors.lastname: Fleming
mesh_terms: D002734:Chlorophyll / Q000737:chemistry*; D000077194:Chlorophyll A; D008274:Magnesium / Q000737:chemistry; D013055:Spectrophotometry, Infrared / Q000379:methods*
chemical_list: D002734:Chlorophyll; C037184:chlorophyll b; D008274:Magnesium; D000077194:Chlorophyll A