0000000000726328

AUTHOR

David Lauvergnat

showing 2 related works from this author

Fast vibrational configuration interaction using generalized curvilinear coordinates and self-consistent basis

2010

In this paper, we couple a numerical kinetic-energy operator approach to the direct-vibrational self-consistent field (VSCF)/vibrational configuration interaction (VCI) method for the calculation of vibrational anharmonic frequencies. By combining this with fast-VSCF, an efficient direct evaluation of the ab initio potential-energy surface (PES), we introduce a general formalism for the computation of vibrational bound states of molecular systems exhibiting large-amplitude motion such as methyl-group torsion. We validate our approach on an analytical two-dimensional model and apply it to the methanol molecule. We show that curvilinear coordinates lead to a significant improvement in the VSC…

Curvilinear coordinatesClassical mechanicsAb initio quantum chemistry methodsChemistryComputationAnharmonicityBound stateAb initioGeneral Physics and AstronomyTorsion (mechanics)Physics::Chemical PhysicsPhysical and Theoretical ChemistryConfiguration interactionThe Journal of Chemical Physics
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Laser control in open molecular systems: STIRAP and Optimal Control

2007

We examine the effect of dissipation on the laser control of a process that transforms a state into a superposed state. We consider a two-dimensional double well of a single potential energy surface. In the context of reactivity, the objective of the control is the localization in a given well, for instance the creation of an enantiomeric form whereas for quantum gates, this control corresponds to one of the transformation of the Hadamard gate. The environment is either modelled by coupling few harmonic oscillators (up to five) to the system or by an effective interaction with an Ohmic bath. In the discrete case, dynamics is carried out exactly by using the coupled harmonic adiabatic channe…

010304 chemical physicsChemistryGeneral Chemical EngineeringStimulated Raman adiabatic passageGeneral Physics and AstronomyContext (language use)General ChemistryOptimal control01 natural sciencesQuantum gateQuantum mechanicsQubit0103 physical sciencesHarmonic010306 general physicsAdiabatic processHarmonic oscillatorJournal of Photochemistry and Photobiology A: Chemistry
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