# 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 *and *photoconductivity*) in both
simple and complex molecular systems. Recent research involves using *density matrix methods with applications to
optical properties and electronic photoconductivity of materials relevant to
photovoltaics*.

### In particular:

## Quantum molecular
dynamics.

### ·
Photoconductivity
in nanostructured semiconductors and in quantum dot arrays.

### ·
Spectra
and dynamics of adsorbates on nanostructured
semiconductor surfaces.

### ·
Energy
transfer, electron transfer and reactions in molecular collisions and at solid
surfaces.

### ·
Intermolecular
forces in ground and excited electronic states.

### ·
Spectra
and dynamics in atomic clusters.

### ·
Photodissociation of polyatomic molecules.

### ·
Photodesorption of molecules from solid surfaces.

### ·
Light
emission in collisions of ions with atoms and solid surfaces.

## Theoretical
methods.

### ·
Time-dependent
many-electron theory; time-dependent molecular orbital and time-dependent Hartree-Fock approaches to molecular phenomena.

### ·
Density
matrix theory of relaxation, dissipation and fluctuations in extended molecular
systems.

### ·
Statistical
mechanics of response and rate processes.

### ·
Few-body
and many-body theory of molecular collisions; collisional time-correlation
approach to many-atom collisions.

## Computational
methods.

### ·
Numerical
methods for the solution of the Liouville-von Neumann
integrodifferential differential equation for the
reduced density operator.

### ·
Integration
of stochastic differential equations for coupled quantal
and classical degrees of freedom, and of the generalized Langevin
equations.

### ·
Integration
of differential equations for coupled electronic and nuclear degrees of
freedom. The "relax-and-drive" method.

### ·
Calculation
of molecular one- and two-electron integrals for travelling atomic basis
functions.

### ·
Numerical
methods for the solution of differential and integral equations of scattering.

### ·
Variational methods for scattering and time-dependent states.

### ·
Path
integral and wavepacket propagation in quantum
dynamics.

### ·
Constrained
simulated annealing and constrained molecular dynamics.

### ·
Operator
algebra methods for solving operator differential equations.

## Computer
visualization and animation of molecular interactions.

### ·
Animation
of the temporal evolution of both nuclear motions and electronic densities
using nuclear trajectories and isocontours of
electronic densities.

### ·
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.