Molecular Quantum Mechanics, an accessible introduction to the foundations of quantum chemistry, established itself as a classic as soon as the original best-selling edition appeared. This new third edition will ensure its place is maintained in the forefront of its field. Entirely rewritten to present the subject more clearly than ever before, this new edition includes two completely new chapters - one on computational techniques in quantum chemistry, and another on scattering theory. Most of the material on the calculations of electronic structure is entirely new, and the discussions in the second edition have been enhanced with more mathematical rigour. With 330 two-colour illustrations, numerous worked examples, in-text exercises, an extensive further information section, and a wide range of applications treated consistently, this will surely prove to be an invaluable book for all senior chemistry undergraduates.