Pris ensemble, les deux volumes offrent une introduction théorique et pratique à la chimie quantique statistique. Ce livre s'adresse à un public spécialisé : étudiants de licence, doctorants, chercheurs...

For all practical purposes the basic physical equations governing the behaviour of a system at the molecular level can only be solved approximately. The key issue in any reliable and accurate computational study in molecular physics and quantum chemistry is the adoption of a suitable model which contains the essential physics and chemistry, is computationally tractable, and preferably amenable to systematic refinement. The provision of advice on the choice of an appropriate model for a specific problem has so far received scant attention. This issue is becoming acute as `standard' software packages are becoming widely available and are being increasingly heavily used in both the academic and industrial sectors by researchers who have received no special training in the theoretical physics and chemistry that underpins them. This volume provides researchers whose background may not be in the computational molecular sciences with the necessary background to make intelligent use of the methods available by performing reliable calculations of appropriate accuracy and making a considered interpretation of the data so obtained.

This volume comprises six chapters which explore the development and applications of the methods of computational chemistry. The first chapter is on new developments in coupled-cluster (CC) theory. The homotopy method is used to obtain complete sets of solutions of nonlinear CC equations. The correspondence between multiple solutions to the CCSD, CCSDT, and full CI equations is established, and the applications of the new approach in modeling molecular systems are discussed. The second chapter reviews the computational theory for the time-dependent calculations of a solution to the Schrödinger equation for two electrons and focuses on the development of propagators to the solution.The next chapter features a discussion on a new self-consistent field for molecular interactions (SCF-MI) scheme for modifying Roothaan equations in order to avoid basis set superposition errors (BSSE). This method is especially suitable for computations of intermolecular interactions. Details of the theory, along with examples of applications to nucleic acid base pair complexes, are given. This chapter is well complemented by the following chapter, which reports the current status of computational studies of aromatic stacking and hydrogen bonding interactions among nucleic acid bases. The next chapter reveals the possibility of calculating the kinetics of chemical reactions in biological systems from the first principles. The last chapter reviews the results of rigorous ab initio studies of the series of derivatives of methane, silane, and germane. The presented molecular and vibrational parameters complement experimental data for these systems. In addition, the theoretical approach allows the prediction of the effects of halogeno-substitutions on their structures and properties.

A comprehensive, extensive textual analysis of the principles of solvent selection and use, the handbook is intended to help formulators select ideal solvents, safety coordinators to protect workers, and legislators and inspectors to define and implement technically correct public safeguards for use, handling, and disposal.

With the central importance of electric polarizability and hyperpolarizability for a wide spectrum of activities, this book charts the trends in the accurate theoretical determination of these properties in specialized fields. The contributions include reviews and original papers that extend from methodology to applications in specific areas of primary importance such as cluster science and organic synthesis of molecules with specific properties./a

Aiming to provide the reader with a general overview of the mathematical and numerical techniques used for the simulation of matter at the microscopic scale, this book lays the emphasis on the numerics, but modelling aspects are also addressed. The contributors come from different scientific communities: physics, theoretical chemistry, mathematical analysis, stochastic analysis, numerical analysis, and the text should be suitable for graduate students in mathematics, sciences and engineering and technology.

Essential Computational Modeling in Chemistry presents key contributions selected from the volume in the Handbook of Numerical Analysis: Computational Modeling in Chemistry Vol. 10(2005). Computational Modeling is an active field of scientific computing at the crossroads between Physics, Chemistry, Applied Mathematics and Computer Science. Sophisticated mathematical models are increasingly complex and extensive computer simulations are on the rise. Numerical Analysis and scientific software have emerged as essential steps for validating mathematical models and simulations based on these models. This guide provides a quick reference of computational methods for use in understanding chemical reactions and how to control them. By demonstrating various computational methods in research, scientists can predict such things as molecular properties. The reference offers a number of techniques and the numerical analysis needed to perform rigorously founded computations. Various viewpoints of methods and applications are available for researchers to chose and experiment with; Numerical analysis and open problems is useful for experimentation; Most commonly used models and techniques for the molecular case is quickly accessible