PHYS 3 |
| Recent time-resolved measurements indicate that radiationless decay of the excited states of solution-phase mononucleotides (which occurs on picosecond or sub-picosecond time scales) is fundamentally different than that of single- or double-stranded oligonucleotides, which exhibit much longer-lived decay components. I will discuss our group's efforts to reveal the nature of excited electronic states in both single- and double-stranded DNA oligomers containing between 2 and 10 nucleic acid bases. Smaller systems are studied using correlated wave functions [CIS(D) and CC2], while larger calculations are possible using recently-developed long-range corrections to time-dependent density functional theory (TD-DFT). Long-range correction eliminates the charge-transfer contamination that otherwise plagues large-scale TD-DFT calculations, and should open up a new size regime to computational electronic spectroscopy. |
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Computational Spectroscopy
8:00 AM-12:05 PM, Sunday, April 6, 2008 Morial Convention Center -- Rm. 342, Oral
Division of Physical Chemistry |