Ab initio quantum chemistry is increasingly paired with computational methods to solve intractable problems in chemistry and molecular physics. Now in a paperback edition, this comprehensive and technical work covers all the important aspects of modern molecular electronic–structure theory, clearly explaining quantum–mechanical methods and applications to molecular equilibrium structure, atomization energies, and reaction enthalpies. Extensive numerical examples illustrate each method described. An excellent resource for researchers in quantum chemistry and anyone interested in the theory and its applications.