The Atom-Atom Potential in Pressure-Broadened Line Width Calculations for XY2-AB: New Expressions in the II(R), II(L), and I(R) Representations.
Abstract
With the help of symbolic manipulations in FORTRAN and MATHEMATICA, we have computerized the procedure for obtaining atom-atom intermolecular potentials from the two-center expansion. We have calculated the atom-atom potential for an XY2 molecule (C2 sub v symmetry) and a linear, AB molecule with the XY2 molecule positioned in the molecule-fixed axes at three different orientations (representations) labeled I sup R, II sup R, II sup L. We have found that the previous development of the atom-atom potential in the II sup R representation is incorrect, leading to a mixed formulation with electrostatic terms in the I sup R and atom-atom terms in the III sup L representation. Broadening-coefficient calculations presented there show that when the correct potential is used anomalous oscillations in the Ka'=1 transitions for O3 broadened by N2 disappear. Further investigation has shown that the variations can be associated with particular quantum symmetries. Improved agreement with the experimental measurements is observed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1993
- Accession Number
- ADA282011
Entities
People
- R. R. Gamache
- S. P. Neshyba
Organizations
- University of Massachusetts Lowell