RESONANT AND NEAR-RESONANT DIPOLE-DIPOLE INTERACTIONS WITH APPLICATION TO PRESSURE-INDUCED SHIFTS OF INFRARED SPECTRAL LINES,
Abstract
The secular equation for a pair of polar molecules undergoing dipole-dipole interaction is studied in detail. Particular attention is paid to accidental near-resonance between non-similar molecules. The secular equation is divided into a part including the near-resonant levels and a part including all other levels; the near-resonant part is diagonalized first, and the coupling to the other part is then treated by second-order perturbation theory. The functional dependence of the perturbed energy levels and wave functions upon the intermolecular distance R and the measure of off-resonance between the near-resonant levels is given explicitly. This analysis is examplified by the interaction between HCl and DCl molecules, where near resonance occurs since the ratio between the rotational constants is approximately 2. The calculation is applied to the shift of the HCl vibration-rotation lines due to DCl pressure, and the oscillation with J of the DCl shifts due to HCl, using a static line-shape theory. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1968
- Accession Number
- AD0687748
Entities
People
- Arieh Rosenberg
- Harry Friedmann
Organizations
- Weizmann Institute of Science