title: Effects of the distributions of energy or charge transfer rates on spectral hole burning in pigment-protein complexes at low temperatures.
abstract: Effects of the distributions of excitation energy transfer (EET) rates (homogeneous line widths) on the nonphotochemical (resonant) spectral hole burning (SHB) processes in photosynthetic chlorophyll-protein complexes (reaction center [RC] and CP43 antenna of Photosystem II from spinach) are considered. It is demonstrated that inclusion of such a distribution results in somewhat more dispersive hole burning kinetics. More importantly, however, inclusion of the EET rate distributions strongly affects the dependence of the hole width on the fractional hole depth. Different types of line width distributions have been explored, including those resulting from Förster type EET between weakly interacting pigments as well as Gaussian ones, which may be a reasonable approximation for those resulting, for instance, from so-called extended Förster models. For Gaussian line width distributions, it is possible to determine the parameters of both line width and tunneling parameter distributions from SHB data without a priori knowledge of any of them. Concerning more realistic asymmetric distributions, we demonstrate, using the simple example of CP43 antenna, that one can use SHB modeling to estimate electrostatic couplings between pigments and support or exclude assignment of certain pigment(s) to a particular state.
authors: Department of Physics, Concordia University, Montreal, Quebec, Canada.
authors: Nicoleta
authors: N
authors: Herascu
authors: Somaya
authors: S
authors: Ahmouda
authors: Rafael
authors: R
authors: Picorel
authors: Michael
authors: M
authors: Seibert
authors: Ryszard
authors: R
authors: Jankowiak
authors: Valter
authors: V
authors: Zazubovich
mesh_terms: D002734:Chlorophyll / Q000378:metabolism*; D004579:Electron Transport; D004735:Energy Transfer; D007700:Kinetics; D008958:Models, Molecular; D016011:Normal Distribution; D045332:Photosystem II Protein Complex / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation; D018724:Spinacia oleracea / Q000201:enzymology; D013696:Temperature
chemical_list: D045332:Photosystem II Protein Complex; C083100:photosystem II, chlorophyll binding protein, CP-43; D002734:Chlorophyll