Ab initio quantum chemistry has emerged as an important tool in chemical research and is appliced to a wide variety of problems in chemistry and molecular physics. Recent developments of computational methods have enabled previously intractable chemical problems to be solved using rigorous quantum-mechanical methods.<br><br> This is the first comprehensive, up-to-date and technical work to cover all the important aspects of modern molecular electronic-structure theory. Topics covered in the book include:<br> * Second quantization with spin adaptation<br><br> * Gaussian basis sets and molecular-integral evaluation<br><br> * Hartree-Fock theory<br><br> * Configuration-interaction and multi-configurational self-consistent theory<br><br> * Coupled-cluster theory for ground and excited states<br><br> * Perturbation theory for single- and multi-configurational states<br><br> * Linear-scaling techniques and the fast multipole method<br><br> * Explicity correlated wave functions<br><br> * Basi