Atomistics & reactivity

The first part of this course presents the basics of quantum chemistry for chemists and physical chemists. It begins by reviewing the principles of quantum mechanics and its master equation, the Schrödinger equation. The resolution of the Schrödinger equation in simple cases and the notions of wave functions and quantization are presented and illustrated in simple cases. The hydrogen atom is then studied.

The teaching also focuses on approximation methods to determine the properties of complex systems where the Schrödinger equation cannot be solved directly. The effect of spin on the electronic properties of atoms and molecules will also be discussed.

The second part of this teaching focuses on the quantum description of molecular properties and reactivity. The qualitative construction of molecular orbitals using symmetry properties will be introduced and the link between molecular orbital diagram and chemical bonding is made. The link between molecular geometry and electronic structure will be discussed. This teaching will then focus on Huckel's method of obtaining molecular orbital diagrams of π systems. The classical notions of conjugation, delocalization, donor or acceptor character and aromaticity will be studied in this approach. The theory of boundary orbitals is used to rationalize molecular reactivity (cycloadditions, electrocyclisation) and molecular geometries.