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Excited states and photodynamics simulations

Mario Barbatti has become Professor at the Institut de Chimie Radicalaire of Aix-Marseille Université in November 2015. Information on his current research is available here. This web page documents the activities of his group at the Max-Planck-Institut für Kohlenforschung (until 2015).

The Born-Oppenheimer approximation is the most fundamental hypothesis in chemistry. On it rests our chemical intuition about molecular structure. In many situations, however, when the molecular system owns enough energy to explore unusual regions of the configuration space, the Born-Oppenheimer approximation may fail. In such regions, the adiabatic surface driving the time evolution of the system branches and the nuclear wavepacket will split among a manifold of states.

The occurrence of these nonadiabatic effects is not only common for a large number of problems, ranging from collision reactions to photochemistry, but it is the basis for key biochemical phenomena, such as light detection and the photostability of the genetic code.

The research in Barbatti's group is mainly focused on nonadiabatic processes that occur after molecular photoexcitation. These investigations are carried out by quantum-chemical calculations and excited-state dynamics simulations. Besides direct applications, the group also works on methodological developments, such as those included in the NEWTON-X program.

Mario Barbatti

Dr. Mario Barbatti

since 2015
Professor at the Institut de Chimie Radicalaire of the Aix-Marseille University, France.
Group leader at the Max Planck Institute für Kohlenforschung
Habilitation University of Vienna
Post-Doc University of Vienna (H. Lischka)
Post-Doc Federal University of Rio de Janeiro (C. E. Bielschowsky)
PhD degree (G. Jalbert)
Master degree (N. V. de Castro Faria)
Physics studies, Federal University of Rio de Janeiro
Born in Petropolis/Brasil

Research Topics

Ultrafast and nonadiabatic phenomena
Ultrafast and nonadiabatic phenomena

Ultrafast and nonadiabatic phenomena

The group interest focuses on ultrafast and nonadiabatic processes, including:

  • Internal conversion
  • Excited-state intramolecular proton transfer
  • Vibrational relaxation

Systems of interest include:

  • Conjugated molecules
  • Aromatic systems
  • Organometallic compounds

As an example of application, with our collaborators in Vienna and in Prague, we have recently completed a comprehensive investigation of the ultrafast processes occurring in all five nucleobases composing DNA and RNA.

Spectrum simulations
Spectrum simulations

Spectrum simulations

Our group has investigated the UV and visible spectrum of a number of molecules. The simulations are performed with a semiclassical method, which allows obtaining absorption cross section in absolute units and includes vibronic couplings.

In a recent investigation, we have used this methodology to show how the anomalous photophysics of urocanic acid, one of the main UV absorbers in our skin, can be explained by tautomeric effects.

Simulation methods
Simulation methods

Simulation methods

The theoretical treatment of the time-dependent nonadiabatic phenomena for molecular systems is a formidable challenge in many levels, from the description of the excited states to the time propagation of their properties. Given that the full quantum mechanical solution of such problems for large molecules is out of question, several semiclassical approaches have been developed in the last half century to tackle the problem.

Our group dedicates to the development of tools for excited-state research, including nonadiabatic dynamics and spectrum simulations. In particular, we are among the main developers of the NEWTON-X program for surface hopping simulations.