This book has evolved from lectures devoted to applications of the Wentzel - Kramers – Brillouin- (WKB or quasi-classical) approximation and of the method of 1/N −expansion for solving various problems in atomic and nuclear physics. The intent of this book is to help students and investigators in this field to extend their knowledge of these important calculation methods in quantum mechanics. Much material is contained herein that is not to be found elsewhere. WKB approximation, while constituting a fundamental area in atomic physics, has not been the focus of many books. A novel method has been adopted for the presentation of the subject matter, the material is presented as a succession of problems, followed by a detailed way of solving them. The methods introduced are then used to calculate Rydberg states in atomic systems and to evaluate potential barriers and quasistationary states. Finally, adiabatic transition and ionization of quantum systems are covered.

the book has been revised to include the postgraduate physics sylabi of indian Universities in addition to the undergraduate honours syllabi covered in the previous edition.Apart from the new addition made in the existing chapters have been added in this edition to deal with the quantum mechanical theories of atomic and molecular structure.

For upper-level undergraduates and graduate students: an introduction to the fundamentals of quantum mechanics, emphasizing aspects essential to an understanding of solid-state theory. Numerous problems (and selected answers), projects, exercises.

This established text contains an advanced presentation of quantum mechanics adapted to the requirements of modern atomic physics. The third edition extends the successful second edition with a detailed treatment of the wave motion of atoms, and it also contains an introduction to some aspects of atom optics that are relevant for current and future experiments involving ultra-cold atoms. Included: Various problems with complete solutions.

This expanded and updated well-established textbook contains an advanced presentationof quantum mechanics adapted to the requirements of modern atomic physics. Itincludes topics of current interest such as semiclassical theory, chaos, atom optics andBose-Einstein condensation in atomic gases. In order to facilitate the consolidationof the material covered, various problems are included, together with completesolutions. The emphasis on theory enables the reader to appreciate the fundamentalassumptions underlying standard theoretical constructs and to embark on independentresearch projects. The fourth edition of Theoretical Atomic Physics contains anupdated treatment of the sections involving scattering theory and near-thresholdphenomena manifest in the behaviour of cold atoms (and molecules). Special attentionis given to the quantization of weakly bound states just below the continuum thresholdand to low-energy scattering and quantum reflection just above. Particular emphasisis laid on the fundamental differences between long-ranged Coulombic potentialsand shorter-ranged potentials falling off faster than 1/r2 at large distances r. The newsections on tunable near-threshold Feshbach resonances and on scattering in two spatialdimensions also address problems relevant for current and future research in the fieldof cold (and ultra-cold) atoms. Graduate students and researchers will find this book avaluable resource and comprehensive reference alike.

Written as a collection of problems, hints and solutions, this book should provide help in learning about both fundamental and applied aspects of this vast field of knowledge, where rapid and exciting developments are taking place.

This text unravels those fundamental physical principles which explain how all matter behaves. It takes us from the foundations of quantum mechanics, through quantum models of atomic, molecular, and electronic structure, and on to discussions of spectroscopy, and the electronic and magnetic properties of molecules.