Optimal initiation of electronic excited state mediated intramolecular H-transfer in malonaldehyde by UV-laser pulses

摘要: Optimally controlled initiation of intramolecular H-transfer in malonaldehyde is accomplished by designing a sequence ultrashort (~80 fs) down-chirped pump-dump ultra violet (UV)-laser pulses through an optically bright electronic excited [S 2 (π π ∗)] state as mediator. The such laser theoretically synthesized within the framework optimal control theory (OCT) and employing well-known scheme Tannor Rice [D.J. Tannor, S.A. Rice, J. Chem. Phys. 83, 5013 (1985)]. In OCT, task framed maximization cost functional defined terms objective function along with constraints on field intensity system dynamics. latter monitored solving time-dependent Schrodinger equation. initial guess, driven dynamics optimized pulse structure (i.e., spectral content temporal profile) followed associated mechanism involved fulfilling are examined detail discussed. A comparative account dynamical outcomes Condon approximation for transition dipole moment versus its more realistic value calculated ab initio also presented.