Issues concerning the primary act of charge generation and transport in the condensed molecular (organic) phase are addressed. These include time resolved studies from nanoseconds to hundreds of femtoseconds of the evolution of the photoexcited electron from quasi-free, to the locally dressed geminate condition, to finally Coulomb-free charge that carries electricity. Condensed phase electronic states near the ionization continuum in neat liquids and in solutions of biologically interesting solute molecules are to be identified. Special double beam time-of-flight probing of migrating photoproduced ions in an electric field is to be initiated in the hope that electronic spectra of charged species can be obtained at the picomolar level. Throughout nonlinear (multiphoton) excitation is used with ultrasensitive conductometric or luminescence detection. Both applied fields and material density are parameters to be varied. The intention is that such work will address the underlying processes in photosynthetic (as well as oxidative) energy storage in biology involving vectorial electricity across membranes and electron transport chains in the molecular condensed phase.
| Shreve, A P; Trautman, J K; Frank, H A et al. (1991) Femtosecond energy-transfer processes in the B800-850 light-harvesting complex of Rhodobacter sphaeroides 2.4.1. Biochim Biophys Acta 1058:280-8 |
| Trautman, J K; Shreve, A P; Violette, C A et al. (1990) Femtosecond dynamics of energy transfer in B800-850 light-harvesting complexes of Rhodobacter sphaeroides. Proc Natl Acad Sci U S A 87:215-9 |
