Computing, Theory and Experiments of
Dynamics and Kinetics Studies of Chemical Processes
Unit: Chemical
Reaction Dynamics (PIs:
P. Casavecchia, N. Balucani)
The dynamics of elementary gas-phase reactions
of a variety of atoms (such as O, N, C, Cl, S) and
radicals (such as OH, C2, CN) with simple as well as complex
molecules (from H2 to hydrocarbons) of interest in atmospheric-,
combustion- and astro-chemistry, are investigated by
using the crossed molecular beam scattering technique with mass-spectrometric
detection. Recently, the technique of the “soft” electron-ionization for
product detection, which permits to suppress the dissociative ionization of
interfering species, has been successfully implemented for the first time. This
technique permits to identify all possible reaction products from a
multi-channel polyatomic reaction, characterize their reaction dynamics, and
determine the branching ratios. Recently, a new laboratory has also been built,
where characterization of the internal quantum states of the atomic and radical
beams used in the crossed beam reactive scattering studies, is accomplished by
using the techniques of Laser-Induced-Fluorescence (LIF) and
Resonance-Enhanced-Multi-Photon-Ionization Time-of-flight
(REMPI-TOF). Very recently, the capability of studying radical + radical
reactions in crossed-beams (such as O + allyl and O +
methyl) has also been developed. For simple systems the experimental results
are often compared with theoretical predictions from quantum and/or quasiclassical scattering calculations on ab initio potential energy surfaces.
Collisional studies are carried out with an
experimental apparatus using effusive and supersonic molecular beam sources, a
rotating slotted disks velocity selector, a magnetic analyzer, a scattering
chamber, and a quadrupole mass spectrometer measuring
beam intensity and its attenuation. Cross section measurements, performed under
high angular and velocity resolution conditions, provide quantitative information
on the intermolecular interaction between projectile and target. A parallel
effort is performed to understand the nature and to model the behavior of the relevant potential energy surfaces.
Applications involve the study of the stereodynamics
of elementary processes in chemical kinetics, laser emission, energy transfer
processes, ionization phenomena, neutral and ion molecular reactions of
interest for combustion, astrophysical chemistry, and
molecular absorption at surfaces of interest for catalysis.
Unit: Computational Dynamics and Kinetics (PI:
A. Lagana')
Design and execution of accurate quantum,
classical and semiclassical calculations of
probabilities, cross sections and rate coefficients of chemical reactions
relevant to the modeling of gas phase processes of
interest for technological and environmental problems (air pollution,
spacecraft re-entry, laser technologies, cold plasmas). Molecular dynamics
approaches to the design and simulation of chemical processes for innovative
materials and biological applications. Design and implementation of algorithms
aimed at estimating observable properties of molecular systems on parallel and
distributed platforms. Management of the COMPCHEM Grid Virtual Organization and
development of software tools for the evaluation of user and service quality. Virtual reality applications to molecular sciences, e-learning and
virtual campuses. Modeling of environmental problems of secondary pollutant production in the
atmosphere.
Unit: Theory of elementary chemical processes (PIs: V. Aquilanti, G. Grossi, S. Cavalli, A. Lombardi)
Quantum and Semiclassical
theory for elementary chemical reactions involving three and four atoms. Hyperspherical harmonics and their
discrete analogues for the quantum treatment of reactive collisions. Theory of nonadiabatic processes, cold
collisions. Hyperspherical approach semiclassical and classical dynamics of
to many-body systems. Chirality manifestations in molecular collisions. Potential energy
surfaces of tetratomic chiral
molecules, internal modes with inversion of chirality.
Atom-chiral molecule collision
simulations. Hyperspherical representation of potential energy surfaces. Quantum and semiclassical spin networks
and application to molecular dynamics and spectroscopy. Exact
calculation and asymptotic approximation of nJ
symbols, detailed properties for n=2,3 and
disentangling of growing complexity spin networks in the classical limit.
Unit: Elementary
reactions in astrochemistry and gas-phase prebiotic chemistry (PI: N. Balucani)
The experimental study of elementary reactions
of interest in astrochemistry and gas-phase prebiotic chemistry is achieved by means of a Crossed
Molecular Beam Apparatus with Mass-Spectrometric detection. The experimental
results are interpreted in the light of ab initio and
RRKM calculations. The implications in the chemical evolution of interstellar
clouds and planetary atmospheres up to prebiotic
molecules are assessed.
Team Members :
Antonio Lagana' (lag@unipg.it) - Full professor
Piergiorgio Casavecchia (piero@dyn.unipg.it) - Full professor
Gaia Grossi (gaia@dyn.unipg.it) - Full
professor
Ferdinando Pirani (pirani@dyn.unipg.it) - Full professor
Vincenzo Aquilanti (aquila@dyn.unipg.it) - Emeritus professor
Giangualberto Volpi - Emeritus Professor
Nadia Balucani (nadia.balucani@unipg.it) - Associate professor
Simonetta Cavalli (cavalli@dyn.unipg.it)
- Associate professor
Stefano Crocchianti - Researcher
Andrea Lombardi (abulafia@dyn.unipg.it)
- Researcher
Noelia Faginas-Lago
(noelia@dyn.unipg.it) - Co.Co.Co.
Leonardo Pacifici (xleo@dyn.unipg.it) - Co.Co.Co.
Alessandro Costantini (alex@dyn.unipg.it) - Co.Co.Co.
Francesca Leonori - Grant Holder
Federico Palazzetti (fede@dyn.unipg.it)
- Grant Holder
Sergio Rampino - Grant Holder
Dimitrios Skouteris (dimitris@dyn.unipg.it) - Grant Holder
Marco Verdicchio (m.verdicchio@gmail.com)
- PhD Student
COLLABORATORS:
Franco Vecchiocattivi, Marzio
Rosi, David Cappelletti, Stefano Falcinelli, Carlo
Manuali, Osvaldo Gervasi, Sergio Tasso (University of Perugia, Perugia,
Italy); Fermin Huarte Larrañaga, Antonio Aguilar,
Margarita Albertí (University
of Barcelona, Spain); Prof. Walther Caminati (University of Bologna, Bologna, Italy); Ernesto García Para, Amaia Saracibar (University of the
Basque Country, Vitoria, Spain); Mario Scotoni (University of Trento, Trento, Italy); L. Vattuone,
M. Rocca-Dipartimento (University of
Genova, Genova, Italy); Mario Capitelli, Savino Longo, Annarita Laricchiuta (University of Bari, Bari, Italy); Michele Alagia,
R. Richter, S. Stranges (Gasphase
Beamline @ Sincrotrone Trieste, Trieste, Italy);
Nazareno Re, Cecilia Coletti (University of Chieti, Chieti, Italy); Elda
Rossi (Cineca, casalecchio
di Reno, Italy), Javier Aoiz, Louis Baňares (University Complutense, Madrid, Spain); Jean-Michel Launay, S. Le Picard. A. Canosa, C. Berteloite, I. R. Sims (University of Rennes
1, Rennes, France); P. Honvault,
B. Pascal-Honvault (University
of Besançon, Besançon, France); M. Costes, A. Bergeat, K. M. Hickson (University of Bordeaux, Bordeaux,
France); W. D. Geppert, M. Hamberg
(University of Stockholm, Stockholm, Sweden); X. Yang (Dalian Institute
of Chemical Physics, Dalian, China); Ralf I. Kaiser (University of Hawaii at Manoa, Honolulu, HI, USA); Roger Anderson (University of California, Santa
Cruz, CA, USA); Robert Littlejohn (University of California, Berkeley, CA, USA); Misha B. Sevryuk (Russia Academy of Science, Moscow, Russia); Florent Calvo, Stefano Evangelisti, Xavier
Gadea (CNRS, France); Ersin
Yurtsever (Koc University, Istanbul, Turkey); Jesus Rubaio Soneira
(University of