Light-induced photodissociation in the lowest three electronic states of the NaH molecule.

It has been known that electronic conical intersections in a molecular system can also be created by laser light even in diatomics. The direct consequence of these light-induced degeneracies is the appearance of a strong mixing between the electronic and vibrational motions, which has a strong fingerprint on the ultrafast nuclear dynamics. In the present work, pump and probe numerical simulations are performed with the NaH molecule involving the first three singlet electronic states (XΣ(X), AΣ(A) and BΠ(B)) and several light-induced degeneracies in the numerical description.

Attosecond Probing of Nuclear Vibrations in the D and HeH Molecular Ions.

We study the ultrafast photodissociation of small diatomic molecules using attosecond laser pulses of moderate intensity in the (extreme) ultraviolet regime. The simultaneous application of subfemtosecond laser pulses with different photon energies─resonant in the region of the molecular motion─allows one to monitor the vibrational dynamics of simple diatomics, like the D and HeH molecular ions. In our real-time wave packet simulations, the nuclear dynamics is initiated either by sudden ionization (D) or by explicit pump pulses (HeH) via distortion of the potential energy of the molecule.

Tracing the vibrational dynamics of sodium iodide the spectrum of emitted photofragments.

We study by real-time wave packet simulations the ultrafast photodissociation dynamics of the sodium iodide molecule with the aim to trace molecular vibrational motion in a bound electronic state. Applying a few-cycle infrared pump laser pulse, a nuclear wave packet is created in the ground electronic state the dynamic Stark shift of the potential energy curves of the molecule. To probe this coherent motion in the ground state, we propose to use a series of ultrashort laser pulses with different photon energies that resonantly promote the spread-out wave packet to the repulsive excited state.

Communication: Substantial impact of the orientation of transition dipole moments on the dynamics of diatomics in laser fields.

The formation of light-induced conical intersections (LICIs) between electronic states of diatomic molecules has been thoroughly investigated over the past decade. In the case of running laser waves, the rotational, vibrational, and electronic motions couple via the LICI giving rise to strong nonadiabatic phenomena. In contrast to natural conical intersections (CIs) which are given by nature and hard to manipulate, the characteristics of LICIs are easily modified by the parameters of the laser field.

Intrinsic and light-induced nonadiabatic phenomena in the NaI molecule.

Nonadiabatic effects play a very important role in controlling chemical dynamical processes. They are strongly related to avoided crossings (AC) or conical intersections (CIs) which can either be present naturally or induced by classical laser light in a molecular system. The latter are named as "light-induced avoided crossings" (LIACs) and "light-induced conical intersections" (LICIs).

Competition between Light-Induced and Intrinsic Nonadiabatic Phenomena in Diatomics.

Nonadiabatic effects arise due to avoided crossings or conical intersections that are either present naturally in field-free space or induced by a classical laser field in a molecule. Recently, it was demonstrated that nonadiabatic effects in diatomics can also be created in an optical cavity. Here, the quantized radiation field mixes the nuclear and electronic degrees of freedom.

Towards controlling the dissociation probability by light-induced conical intersections.

Light-induced conical intersections (LICIs) can be formed both by standing or by running laser waves. The position of a LICI is determined by the laser frequency while the laser intensity controls the strength of the nonadiabatic coupling. Recently, it was shown within the LICI framework that linearly chirped laser pulses have an impact on the dissociation dynamics of the D molecule (J.

Tracking the photodissociation probability of D(2)(+) induced by linearly chirped laser pulses.

In the presence of linearly varying frequency chirped laser pulses, the photodissociation dynamics of D2(+) is studied theoretically after ionization of D2. As a completion of our recent work [A. Csehi et al.

Photodissociation of D2 (+) induced by linearly chirped laser pulses.

Recently, it has been revealed that so-called light-induced conical intersections (LICIs) can be formed both by standing or by running laser waves even in diatomic molecules. Due to the strong nonadiabatic couplings, the existence of such LICIs has significant impact on the dynamical properties of a molecular system. In our former studies, the photodissociation process of the D2 (+) molecule was studied initiating the nuclear dynamics both from individual vibrational levels and from the superposition of all the vibrational states produced by ionizing D2.

Influence of light-induced conical intersection on the photodissociation dynamics of D2(+) starting from individual vibrational levels.

Previous works have shown that dressing of diatomic molecules by standing or by running laser waves gives rise to the appearance of so-called light-induced conical intersections (LICIs). Because of the strong nonadiabatic couplings, the existence of such LICIs may significantly change the dynamical properties of a molecular system. In our former paper (J.

The effect of chemical substituents on the functionality of a molecular switch system: a theoretical study of several quinoline compounds.

This study investigates the effect of chemical substituents on the functional properties of a molecular photoswitch (Phys. Chem. Chem.