Lab Home | Phone | Search
Center for Nonlinear Studies  Center for Nonlinear Studies
 Colloquia Archive 
 Postdoc Seminars Archive 
 Quantum Lunch 
 Quantum Lunch Archive 
 CMS Colloquia 
 Q-Mat Seminars 
 Q-Mat Seminars Archive 
 P/T Colloquia 
 Kac Lectures 
 Kac Fellows 
 Dist. Quant. Lecture 
 Ulam Scholar 
 CNLS Fellowship Application 
 Student Program 
 Past Visitors 
 History of CNLS 
 Maps, Directions 
 CNLS Office 
Thursday, April 05, 2012
2:00 PM - 3:00 PM
CNLS Conference Room (TA-3, Bldg 1690)

Student Seminar

Modeling of non-adiabatic photoinduced dynamics in conjugated molecules

Tammie Nelson
T-1 and CNLS

Non-adiabatic dynamics generally defines the entire evolution of electronic excitations in optically active molecular materials. It is commonly associated with a number of fundamental and complex processes such as intraband relaxation, energy transfer and light-harvesting influenced by the spatial evolution of excitations, and transformation of photoexcitation energy into electrical energy via charge separation (e.g., charge injection at interfaces). To treat ultrafast excited state dynamics and exciton/charge transport we have developed non-adiabatic excited state molecular dynamics (NA-ESMD) framework incorporating quantum transitions. Our calculations rely on the actual potential energy surfaces of the excited states combined with the Tully's fewest switches algorithm for surface hopping. This method is applied to model the photoinduced dynamics of distyrylbenzene (a small oligomer of polyphenylene vinylene, PPV). In addition, nonadiabatic molecular dynamics simulations require a large number of independent trajectories and simulation relies on different parameters that should be tested and compared. The chosen parameters can sometimes lead to unanticipated changes in the accuracy of the simulated dynamics.

Host: Kipton Barros, T-4 and CNLS