Theory of dynamic solvent effects on the raman scattering cross section and resonance profiles ofpolyatomic molecules in solution

Bandshape Parameters' Dependence on Solvent in Raman Excitation Profiles, and Absorption Spectra of Violaxanthin and Lutein

The experimental results of resonance Raman excitation profiles (RREPs) for the Ω1, Ω2, and Ω3 vibrations of violaxanthin and lutein in acetone, toluene, and carbon disulfide have been interpreted in terms of an improved vibronic interaction theory. The bandshape parameters from RREPs have been employed for the calculation of absorption spectra. Excellent agreement between calculated and observed RREPs and absorption spectra was found. However, the results obtained for RREPs of lutein in carbon disulfide deviate considerably from experiment. The results indicate that the major broadening mechanism is homogeneous in carbon disulfide, whereas the broadening in acetone and toluene includes contributions from both homogeneous and inhomogeneous mechanisms.

Resonance effects in strongly exothermic long-range electron transfer and their possible implications for the behaviour of site-directed mutant proteins

Long-range electron transfer investigations of hemoproteins, blue copper and iron-sulphur proteins frequently rest on electronically excited metal centres. When the excitation energy approaches the oxidation or reduction potentials of intermediate residues the superexchange view normally used, however, fails and a variety of new dynamic features arise. These all involve population of the intermediate cation or anion residue states which can be partially or wholly vibrationally relaxed. We discuss suitable views and a new theoretical formalism for these phenomena. We also note some important implications for site-directed mutagenesis in long-range, strongly exothermic electron transfer processes.