Chemistry

The program of the course includes a cycle of lectures (40 hours) to acquire the basic theoretical knowledge on the dynamics of chemical reactions and the connection with macroscopic kinetics, and a cycle of laboratory experiences using the Photofragment Translational Spectroscopy technique (12 hours). The topics covered in the course are as follows. Definition of a chemical reaction rate, order and molecularity of a reaction, determination of the order of a reaction (2 hours). Elements of chemical kinetics, reversible, irreversible, parallel and consecutive reactions, etc. (4 hours). Temperature dependence of the rate constants and the Arrhenius equation, reaction mechanisms and molecular dynamics, exact analytical solution of complex reactions, approximate methods, examples of mechanisms of complex reactions (2 hours). Molecular collisions: elastic, inelastic and reactive; reaction cross section and reaction probability (2 hours). Relationship between microscopic dynamics and macroscopic kinetics, the principle of microscopic reversibility and that of the detailed balance (2 hours). Potential energy surfaces and their characteristics, from PES to reaction dynamics (2 hours). Energy distribution in exoergic reactions (attractive and repulsive PES), energy requirements for reactions with a barrier (2 hours). Dynamics of bimolecular collisions, reactive collisions, opacity function, steric factor, angular distribution in reactive collisions (4 hours). The reaction F + H2 - HF + H, the crossed molecular beams technique, example of a state-to-state kinetics: the reaction F + H2 (2 hours). Statistical approach to reaction dynamics: Transition State Theory (2 hours). Unimolecular reactions and RRKM theory (6 hours). Supersonic molecular beams (3 hours). Experimental techniques for the study of chemical reactions dynamics (2 hours). Photofragment Translational Spectroscopy (3 hours). Allyl radical photodissociation at 248 nm (4 hours). Laboratory experience: measurement of the velocity distribution of noble gases supersonic molecular beams and study of allyl radical or of an alkyl nitrite photodissociation at 248 nm by photofragment translational spectroscopy.

Knowledge of basic chemistry, basic mathematics, basic physics, quantum mechanics (course of Physical Chemistry II), classical kinetics and statistical thermodynamics.

1) J.I. Steinfeld, J.S. Francisco, W.L. Hase, Chemical Kinetics and Dynamics, Prentice Hall, Englewood Cliffs, New Jersey (1989). 2) Lecture notes.

Attendance of classroom lessons is optional. Laboratory attendance is mandatory.

The final evaluation will be based on an oral test in which the student will have to show that he/she has learned the concepts explained during the course.

The course is organized in lectures for 5 CFU (40 hours) and laboratory experiences for 1 CFU (12 hours). During the frontal hours the theoretical aspects of chemical reaction dynamics and the existing relationships with macroscopic kinetics will be treated. In the laboratory hours practical experiences will be carried out with the technique of Photofragment Translational Spectroscopy. Attendance of classroom lessons is optional. Laboratory attendance is mandatory.