Molecular wave-packet dynamics on laser-controlled transition states

Abstract

We present a kinematically complete and time-resolved study of the dissociation dynamics of H 2 + using ultrashort extreme-ultraviolet and near-infrared laser pulses. The reaction kinematics can be controlled by varying the time delay between the two pulses. We demonstrate that a time-dependent laser-dressed potential-energy curve enables the control of the nuclear motion. The dynamics is well reproduced by intuitive semiclassical trajectories on a time-dependent potential curve. From this most fundamental scenario we gain insight in the underlying mechanisms which may be applied as design principles for molecular quantum control, particularly for ultrafast molecular reactions involving the motion of protons

Symmetry breaking in the body-fixed electron emission pattern due to electron-retroaction in the photodissociation of H2+ and D2+ close to threshold

“…on the photodissociation of doubly excited (Q2) states of hydrogen molecules with [17] and without [8] external fields, as mentioned in the Introduction.…”

“…As an example, in Fig. 5 we plot the asymmetry as the yield of the energy correlation map, spanned by the KER versus the photoelectron kinetic energy E e for the direct dissociative ionization of H 2 molecules by a single linearly polarized photon with an energy of 33 eV (compare to [17]) in the absence of any internal or external fields. Note that in this case the asymmetry is only the difference between the yields along the proton and hydrogen directions (n H + − n H ); for visual clarity in this spectrum the difference has not been normalized to the sum of both yields (n H + + n H ).…”

Functional Mode Singlet Fission Theory

“…In a recent “pump-and-probe” experiment, significant vibrational coherence transfer was observed in a TIPS-pentacene thin film at five distinct phonon bands. Because the phonon frequencies extend up to 1576 cm –1 , it is technically possible to engineer the formation of correlated triplet pairs through photoexcitation with time-delayed sub-10 fs control laser pulses . Moreover, restricted active-space calculations of potential energy profiles for tetracene derivatives suggest that their electronic coupling strengths are likely to undergo fluctuations commensurate with molecular vibrations .…”

Sub-10-fs control of dissociation pathways in the hydrogen molecular ion with a few-pulse attosecond pulse train

“…This is because their simplest structures consisting of two protons and one or two (H 2 ) electrons should provide benchmarks for the fundamental characteristics of electronic 20 21 and nuclear dynamics 19 32 33 in the sub-femtosecond and 10-fs regimes, respectively. In fact, XUV IAP pump and near-infrared probe experiments have revealed the vibrational motion of and the time evolution of the coherent superposition of multiple electronic states in (refs 19 , 20 , 34 ). An XUV attosecond pulse train (APT) composed of discrete HH components has also been useful for investigating the electronic states in H 2 and (refs 21 , 24 ).…”