Theory, Practice and Techniques in Quantum Chemistry

Quantum chemistry deals with the application of quantum mechanical principles and equations to the study of molecules. In order to understand matter at its most fundamental level, we must use quantum mechanical models and methods. There are two aspects of quantum mechanics that make it different from previous models of matter. The first is the concept of wave-particle duality; that is, the notion that we need to think of very small objects (such as electrons) as having characteristics of both particles and waves. Second, quantum mechanical models correctly predict that the energy of atoms and molecules is always quantized, meaning that they may have only specific amounts of energy. Quantum chemical theories allow us to explain the structure of the periodic table, and quantum chemical calculations allow us to accurately predict the structures of molecules and the spectroscopic behavior of atoms and molecules. These days, it is easy to calculate, using quantum chemical principles, what happens within a molecule of up to 400 atoms. Using simplified models, it is possible to study molecules with thousands of atoms.

This text entitled ‘Theory, Practice and Techniques in Quantum Chemistry’ presents current developments in this rapidly developing field that falls between the historically established areas of mathematics, physics, chemistry, and biology. It is intended to provide comprehensive treatment of the use of the symmetric group in quantum chemical structures of atoms, molecules, and solids. Quantum chemical calculations have been used to solve big mysteries in space. Quantum chemical calculations are needed to explain what happens to the electrons’ trajectories within a molecule and the quantum chemical calculations solve the Schrödinger equation for molecules. This book is designed to help the students to achieve a basic understanding of the underlying concepts of quantum chemistry.