Breakdown of the Born-Oppenheimer Approximation in Diatomic Molecules
Lectures by Professor Robert Field
This lecture series was offered during January 2005 as a follow-up to topics covered in 5.74. Attendance was voluntary and open to any students with a background in quantum mechanics (5.61 or equivalent) and an interest in molecular dynamics.
Introduction to the Spectroscopic Effective Hamiltonian
The Born-Oppenheimer approximation and matrix elements of terms in the effective molecular Hamiltonian that violate the BO approximation. Vibration, rotation, spin-orbit, interelectronic interaction. Hund's coupling cases.
Spectroscopic Pertubations, Predissociation, and Autoionization
Introduction to dynamical processes.
Semiclassical Methods for Calculating Vibrational Overlap Integrals
All coupling processes are mediated by vibrational overlap integrals, which are computed numerically. Semiclassical calculation of overlaps reveals physical factors controlling computed values: the length of the stationary phase region is controlled by the slopes of the potential curves at the intersection and the velocity in the crossing region.
Wavepackets and Landau-Zener
What happens in the vicinity of a curve crossing?