RESEARCH INTERESTS
Our research deals with theoretical and computational aspects of molecular
and materials sciences, with emphasis on the unified treatment of physical
and chemical kinetics using quantum molecular dynamics. It includes collision-induced
and photoinduced phenomena in the gas phase, clusters, and at solid surfaces.
Our aim is to provide a fundamental approach to molecular dynamics, where
electronic and nuclear motions are consistently coupled to account for quantal
effects. We use quantum and statistical mechanics, mathematical, and
computational methods, to describe time-dependent phenomena (such as femtosecond
dynamics and spectra) in both simple and complex molecular systems.
In particular:
Quantum molecular dynamics.
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Spectra and dynamics of adsorbates on
nanostructured surfaces.
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Energy transfer, electron transfer and reactions
in molecular collisions and at solid surfaces.
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Intermolecular forces in ground and excited
electronic states.
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Spectra and dynamics in atomic clusters.
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Photodissociation of polyatomic molecules.
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Photodesorption of molecules from solid
surfaces.
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Light emission in collisions of ions with atoms
and solid surfaces.
Theoretical methods.
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Time-dependent many-electron theory;
time-dependent molecular orbital and time-dependent Hartree-Fock approaches to
molecular phenomena.
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Density matrix theory of relaxation, dissipation
and fluctuations in extended molecular systems.
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Statistical mechanics of response and rate processes.
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Few-body and many-body theory of molecular
collisions; collisional time-correlation approach to many-atom collisions.
Computational methods.
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Numerical methods for the solution of the
Liouville-von Neumann differential equation for the density operator.
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Integration of stochastic differential equations
for coupled quantal and classical degrees of freedom, and of the generalized
Langevin equations.
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Integration of differential equations for
coupled electronic and nuclear degrees of freedom. The "relax-and-drive"
method.
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Calculation of molecular one- and two-electron
integrals for travelling atomic basis functions.
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Numerical methods for the solution of
differential and integral equations of scattering.
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Variational methods for scattering and time-dependent
states.
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Path integral and wavepacket propagation in
quantum dynamics.
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Constrained simulated annealing and constrained
molecular dynamics.
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Operator algebra methods for solving operator
differential equations.
Computer visualization and animation of molecular interactions.
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Animation of the temporal evolution of both
nuclear motions and electronic densities using nuclear trajectories and
isocontours of electronic densities.
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Animation of electronic transitions and electron
transfer obtained from time-dependent molecular orbitals.
·
Animation of light emission in collisions of
ions involving electronic rearrangement and the related transient dipoles.