Chemical sciences
Study-unit Code
Theoretical chemistry and computational modelling
Giovanni Bistoni
  • Giovanni Bistoni
  • 73 ore - Giovanni Bistoni
Course Regulation
Coorte 2023
Learning activities
Discipline chimiche inorganiche e chimico-fisiche
Academic discipline
Type of study-unit
Obbligatorio (Required)
Type of learning activities
Attività formativa monodisciplinare
Language of instruction
Quantum chemistry plays a key role in international chemical research. By exploiting the methods of theoretical chemistry, it enables the calculation of structures, energies, interactions, and properties of molecules, thus contributing to the development of new drugs, catalysts and functional materials.
The aim of this course is to present and explain, at an advanced level, the theoretical methods commonly used in quantum chemistry to solve chemical problems.
Reference texts
Handouts provided by the lecturer, exercises and computational tutorials.

A. Szabo, Neil S. Ostlund. Modern Quantum Chemistry: Introduction to Advanced Electronic Structure Theory
Educational objectives
Upon completion of the course, students will be able to:
-Explain basic principles and postulates of quantum theory;
-Explain the theoretical foundations, application areas and limitations of modern electronic structure methods commonly used in chemical research;
-Choose the most suitable computational method for any given chemical problem;
-Implement simple electronic structure methods (Hartree Fock, DFT).
A basic knowledge of general chemistry, physical chemistry and inorganic chemistry is required. Knowledge (even rudimentary) of at least one programming language is recommended.
Teaching methods
The course is organized in a series of lectures and computational exercises.
Other information
Please feel free to contact the lecturer for additional information, or for questions concerning the suggested requirements.
Learning verification modality
Oral exam.
Extended program
General introduction to quantum theory: Fundamental postulates, eigenvalues and eigenfunctions, observables and operators, the variational principle, the Helmann-Feynman theorem, Heisemberg relations, stationary states, symmetry and conservation laws, the measurement process.

Introduction to the electronic problem:
Atomic units, the Hamiltonian, separability, the Born-Oppenheimer approximation, electronic wave functions, orbitals, antisymmetry, Slater determinants, spin, electron density, energy of a determinant, the Hartree-Fock approximation, excited determinants, the exact electronic wave function, second quantization.

Wavefunction-based electronic structure methods:
The Hartree-Fock equations and their derivation, Coulomb and exchange operators, Fock operator, properties of the Hartree-Fock wavefunction, Koopman's theorem, Brillouin's theorem, basis sets, Roothan equations, two-electron integrals and their approximations, the SCF procedure. Consequences of the spin: UHF vs ROHF. Limitations of the Hartree-Fock method. The electron correlation. Configuration interaction, complete CI and its truncation. Limitations of CI. Perturbation theory, RSPT series. Analysis, calculation and representation of RSPT terms. Møller-Plesset Perturbation Theory and its limitations. The cluster expansion of the wavefunction, introduction to the coupled cluster method, a brief outline of the CCSD(T) method. An introduction to local correlation methods. Introduction to MCSCF methods, with emphasis on CASSCF and CASPT2. A brief introduction to multi-reference coupled cluster theories.

Density Functional Theory (DFT):
Hohenberg and Kohn theorems, the Kohn-Sham method, modern exchange-correlation functionals. The Jacobs ladder, from LDA to double hybrid. Van der Waals corrections.
Condividi su