Code: WOC	Time Slot/Poster Number: 10:30 - 11:00 am	Session: Raman Theory & PES Calculations
Theoretical Prediction of Raman and ROA spectra
Michael Frisch
Gaussian, Inc., Wallingford, CT
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Summary
Recent developments in the prediction of vibrational Raman and ROA will be presented, with an emphasis on methods which are applicable to larger molecules and on the inclusion of solvent effects. The accuracy of the models for both gas-phase and solution spectra will be evaluated.

Code: WOC	Time Slot/Poster Number: 11:00 - 11:30 am	Session: Raman Theory & PES Calculations
Tackling Non-Adiabatic Effects by Time-Dependent Density Functional Theory
Filipp Furche1; Enrico Tapavicza1; Robert Send2
1UC Irvine, Irvine, CA; 2Karlsruher Institut für Technologie, Karlsruhe, Germany
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Summary
I will summarize a recent time-dependent density functional response theory approach to non-adiabatic couplings which builds on analytical excited state gradient methods. Benchmarks show an insignificant increase in total computation times if the non-adiabatic couplings are evaluated during an excited state gradient calculation. This makes non-adiabatic couplings in systems with well over 100 atoms routinely available. I will present an efficient non-adiabatic molecular dynamics method based on these techniques which uses Gaussian basis functions and does not require explicit propagation of the electronic wavefunction. Applications will include excited state non-radiative lifetimes and photo-induced electrocyclic reactions.

Code: WOC	Time Slot/Poster Number: 11:30 am - 12:00 pm	Session: Raman Theory & PES Calculations
Vibronic Interactions in Semiconducting and Metallic Quantum Dots, Carbon Nanotubes, and Graphene Nanoribbons: Time-Domain Ab Initio Studies
Oleg Prezhdo
University of Washington, Seattle, WA
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Summary
Device miniaturization requires an understanding of the dynamical response of materials on the nanometer scale. A great deal of experimental and theoretical work has been devoted to characterizing the electronic and vibrational dynamics in a variety of novel materials, including carbon nanotubes, graphene nanoribbons, quantum dots, conducting polymers, inorganic semiconductors and molecular chromophores. We have developed state-of-the-art non-adiabatic molecular dynamics techniques and implemented them within time-dependent density functional theory in order to model the ultrafast photoinduced processes in these materials at the atomistic level, and in real time.

Code: WOC	Time Slot/Poster Number: 12:00 - 12:30 pm	Session: Raman Theory & PES Calculations
Modeling of Non-adiabatic Photoinduced Dynamics and Energy Transfer in Conjugated Molecules
Sergei Tretiak1; Sebastian Fernandez-Alberti2; Adrian Roitberg3
1Los Alamos National Laboratory, Los Alamos, NM; 2Universidad Nacional de Quilmes, Bernal, Argentina; 3Department of Chemistry, University of Florida, Gainesville, Florida
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Summary
This talk will overview several applications of recently developed excited state molecular dynamics framework incorporating non-adiabatic quantum transitions studying ultrafast dynamics and exciton transport in several conjugated molecular systems. Our calculations use the CEO semiempirical package combined with the Tully’s fewest switches algorithm for surface hopping probing non-adiabatic processes. Our analysis shows intricate details of photoinduced vibronic relaxation and identify the conformational degrees of freedom leading to ultrafast dynamics and energy transfer. This theoretical modeling allows us to understand and to potentially manipulate energy transfer pathways in molecular materials suitable for solar energy conversion.