Applications of spectral hole burning spectroscopies to antenna and reaction center complexes.

The underlying principles of spectral hole burning spectroscopies and the theory for hole profiles are reviewed and illustrated with calculated spectra. The methodology by which the dependence of the overall hole profile on burn wavelength can be used to reveal the contributions from site inhomogeneous broadening and various homogeneous broadening contributions to the broad Qy-absorption bands of cofactors is emphasized. Applications to the primary electron donor states of the reaction centers of purple bacteria and Photosystems I and II of green plants are discussed.

Spectral hole burning of the primary electron donor state of Photosystem I.

Persistent photochemical hole burned profiles are reported for the primary electron donor state P700 of the reaction center of PS I. The hole profiles at 1.6 K for a wide range of burn wavelengths (λB) are broad (FWHM∼310 cm(-1)) and for the 45:1 enriched particles studied exhibit no sharp zero-phonon hole feature coincident with λB.