Charge transfer induced proton-coupled electron transfer

PHYS 331

Jared J. Paul, jpaul@unc.edu, Brittany C. Westlake, westlake@email.unc.edu, M. Kyle Brennaman, kyleb@email.unc.edu, John M. Papanikolas, john_papanikolas@unc.edu, and Thomas J. Meyer, tjmeyer@email.unc.edu. Department of Chemistry, University of North Carolina at Chapel Hill, Caudill and Kenan Laboratories, Chapel Hill, NC 27599-3290
The relaxation dynamics of a photoexcited hydrogen bound 4-hydroxy-4'-nitrobiphenyl and t-butylamine association complex have been followed using both femtosecond and nanosecond transient absorption spectroscopy. Upon photoexcitation, the biphenyl molecule undergoes an intramolecular transition that transfers charge from the hydroxy end of the molecule to the nitro- end. Ultrafast measurements show direct evidence that relaxation to ground state (i.e. back electron transfer) is coupled to proton transfer from the hydroxyl group to the base. Partitioning to a second path involving dissociation of the hydrogen-bonded complex to give a deprotonated form is shown through nanosecond transient absorption spectroscopy.
 

PHYS Poster Session - Optical Probes of Dynamics in Complex Environments
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Sci-Mix

Division of Physical Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008