Atomic and Molecular Spectra and Lasers- This book aims at undergraduate and postgraduate syllabi of Indian Universities. The book is divided into 19 chapters. It deals with basic aspects of spectroscopy, Bohr’s Theory and relativistic correction, origin of spectral lines and line width broadening mechanisms, angular momentum and vector model of the atom, spin orbit interaction and hydrogen fine structure, alkali spectra and fine structure, Zeeman, Paschen-Back and Stark effects, nuclear spin and hyperfine structure, basic aspects of molecular spectroscopy, rotational spectra, vibrational spectra, molecular electronic spectra, Raman effect, rotation and vibration-rotation Raman spectra, symmetry elements and symmetry operations, orthogonality theorem and character tables, nuclear magnetic resonance, electron spin resonance, Fourier transform spectroscopy, photo-acoustic spectroscopy, Mössbauer spectroscopy and lasers. Key Features • Emphasis has been laid on concepts • Mathematical steps provided to elucidate concepts • Questions at the end of each chapter for developing better understanding of the subject.