Quantum dynamics of molecular systems. Spectroscopy. Large amplitude motions. Curvilinear coordinates.


UCL Promotor : André Nauts

External Collaborators : Fabien Gatti (CTMM, Montpellier II, F), Yves Justum et David Lauvergnat (LCP, Paris-Sud, Orsay, F)

                          Quantuum Nauts

The subject of this research topic is the rigorous application of the fundamental principles of quantum physics to the accurate description of the dynamics of relatively large molecular systems (number of atoms up to about ten) in time-resolved approaches (molecular photoabsorption and photodissociation, tunnelling, propagation of wave packets), in spectroscopy (either resolved in frequency or in time, in presence of a laser field or not), in reactivity…
The theoretical results as well as the codes obtained and used so far have reached such a degree of generality, robustness and versatility, that they can be implemented , if not routinely yet, nevertheless without major difficulties, to simulate some accurate experimental results (for instance, the IR spectrum of the protonated water dimer).

Theoretical tools : analytically as well as numerically exact expressions of the molecular hamiltonian operators in terms of generalized coordinates well-adapted to the processes under study.
Applications: floppy molecules with torsional motion, inversion motion …
Some theoretical results have also led to pedagogical extensions (summer schools and a pedagogical publication concerning unusual commutation relations in physics).