This third edition of Peter Bernath's successful Spectra of Atoms and Molecules is designed to provide advanced undergraduates and graduate students a working knowledge of the vast field of spectroscopy. Also of interest to chemists, physicists, astronomers, atmospheric scientists, and engineers, this volume emphasizes the fundamental principles of spectroscopy with the primary goal of teaching the interpretation of spectra. Features include a presentation of group theory needed to understand spectroscopy, detailed worked examples and a large number of excellent problems at the end of each chapter. Prof. Bernath provides a large number of diagrams and spectra which have been specifically recorded for this book. Molecular symmetry, matrix representation of groups, quantum mechanics, and group theory are among the topics covered; atomic, rotational, vibrational, electronic and Raman spectra are analyzed. Bernath's clear treatment of the confusing topic of line strengths as needed for quantitative applications is featured.This much-needed new edition has been updated to include the 2010 CODATA revision of physical constants, and a large number of corrections and clarifications. Responding to student requests, the main new feature is the addition of detailed worked examples in each chapter. Spectra of Atoms and Molecules, 3e will help demystify spectroscopy by showing readers the necessary steps in a derivation, as well as the final result.