Molecular Spectroscopy
Second year
Hilary Term 2003
Dr Frank Schreiber
6 lectures
This course concerns the spectroscopy of molecules, concentrating on
isolated species in the gas phase, although some of the concepts are
applicable also to condensed matter problems. The course concentrates on
excitation of rotational and vibrational motion, as opposed to electronic
excitation, covered in the "Valence" and "Photochemistry" course. It builds
upon the "Quantum Mechanics" and the "Molecular Energy Levels" course.
Primary information from the spectra obtained includes moments of
inertia and hence bond lengths and angles, bond force constants and
dissociation energies, dipole moments and hence electron distributions. In
addition, in condensed matter information about the orientation or the
environment of the molecules is of interest.
- Introduction
Energy levels of molecules; Born-Oppenheimer separation; interaction of
radiation with matter; absorption; emission; transition moments;
selection rules
- Rotational Spectroscopy (Microwaves)
Rotors and their symmetry; moments of inertia; isotope effects;
centrifugal distortion; selection rules; Stark effect
- Vibrational Spectroscopy (Infrared)
Selection rules; anharmonicity; rotation-vibration transitions; normal
mode vs. local mode; overtone and combination bands
- Raman Spectroscopy
Stokes, Anti-Stokes and Rayleigh scattering; rotational and vibrational
transitions; selection rules; mutual exclusion in centrosymmetric
molecules; Raman vs. IR
- Selected Topics
Experimental methods; effects of nuclear spin statistics; applications
and examples
Problems
Books
- J M Brown, Molecular Spectroscopy (OUP Primer 55)
- P W Atkins, Physical Chemistry
- P W Atkins / R S Friedman, Molecular Quantum Mechanics
- C N Banwell / E M McCash, Fundamentals of Molecular Spectroscopy
- J M Hollas, Modern Spectroscopy
- H Haken / H C Wolf, Molecular Physics and Elements of Quantum
Chemistry
- W Demtröder, Laser Spectroscopy