Conformational dynamics of photoexcited conjugated molecules.
Time-dependent photoexcitation and optical spectroscopy of pi-conjugated molecules is described using a new method for the simulation of excited state molecular dynamics in extended molecular systems with sizes up to hundreds of atoms. Applications are made to poly(p-phenylene vinylene) oligomers. Our analysis shows self-trapping of excitations on about six repeat units in the course of photoexcitation relaxation, identifies specific slow (torsion) and fast (bond-stretch) nuclear motions strongly coupled to the electronic degrees of freedom, and predicts spectroscopic signatures of molecular conformations.
Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA. serg@lanl.gov
S
S
Tretiak
A
A
Saxena
R L
RL
Martin
A R
AR
Bishop