IMPROVED ANALYSIS OF THE ROTATION SPECTRUM OF META-CHLOROTOLUENE USING A FREE ROTOR BASIS AND NON-PERTURBATIVE HYPERFINE TREATMENT

Westerfield, J. H.

Permalink

https://hdl.handle.net/2142/122608 Copy

Description

Title

IMPROVED ANALYSIS OF THE ROTATION SPECTRUM OF META-CHLOROTOLUENE USING A FREE ROTOR BASIS AND NON-PERTURBATIVE HYPERFINE TREATMENT

Author(s)

Westerfield, J. H.

Contributor(s)

• Crabtree, Kyle N.
• Worthington-Kirsch, S E

Issue Date

2023-06-19

Keyword(s)

• Large amplitude motions
• internal rotation

Abstract

Using the soon to be publicly available westerfit package, the rotational spectrum of meta-chloro-toluene has been re-examined. This program allows for treatment of a Cs molecule with an arbitrary-fold internal rotor and a single strong spin source which makes meta-chloro-toluene a promising test case for the code. Unlike other programs designed for internal rotation with spin effects, westerfit includes matrix elements off-diagonal in N rather than the perturbative treatment of the spin-rotation and quadrupole interactions. This allows fitting of all symmetrically allowed terms in both the spin-rotation and the quadrupole tensors as well as inclusion of any higher order terms coupling the large amplitude motion to the spin angular momentum. Meta-chloro-tolune is a particularly challenging case for internal rotor packages due to the low V₃ term coupled to a large V₆ term as well as the spin 3/2 nucleus. Previous attempts to fit this moleculeᵃ were complicated by XIAM’s limitations at very low barrier heights and perturbative quadrupole treatment. This work presents a more complete treatment of the meta-chloro-toluene spectrum and demonstrates comparisons between westerfit and other programs.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Handle URL

https://hdl.handle.net/2142/122608

DOI

https://doi.org/10.15278/isms.2023.7117

Owning Collections