Picosecond isomerization in photochromic ruthenium and osmium polypyridine complexes containing chelating sulfoxides

INOR 249

Jeffrey J. Rack, rack@helios.phy.ohiou.edu, Aaron A. Rachford, ar965801@ohiou.edu, Nicholas V. Mockus, nm118701@ohiou.edu, Seth L. Marquard, sm159502@ohio.edu, and Dennis P. Butcher Jr., db154203@ohio.edu. Department of Chemistry and Biochemistry, Ohio University, Athens, OH 45701
Photochromic compounds are molecular devices which convert photonic energy to potential energy, which is employed in bond-breaking and bond-making processes. Our examinations of ruthenium and osmium polypryridine complexes containing monodentate sulfoxide and chelating sulfoxide ligands demonstrate that S-to-O isomerization is efficient, and can occur rapidly in the solid state. For example, the isomerization quantum yield may vary from <0.0001(1) in [Ru(tpy)(acac)(dmso)]+ (tpy is 2,2′:6′,2″-terpyridine; acac is acetylacetonate) to 0.80(1) in [Ru(tpy)(Mepic)(dmso)]2+ (Mepic is 6-methyl-2-pyridinecarboxylate). In accord with these data, picosecond transient absorption spectroscopic data show that S-to-O isomerization time constant may be as fast as 80 ps. Recent studies of ruthenium polypyridine complexes containing chelating sulfoxides illustrate that efficient energy conversion may also be achieved. In conjunction with nanosecond and picosecond transient absorption spectroscopy data, structural and electrochemical data will be presented as well as a structural model to understand the photochemistry and photophysics of these compounds.
 

Frontiers of Inorganic Chemistry: The Gray Areas
7:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Inorganic Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006