Many-body perturbation theory electronic structure calculations for the methoxy radical. I. Determination of Jahn-Teller energy surfaces, spin-orbit splitting, and Zeeman effect
Abstract
Many-body perturbation theory calculations of the electronic structure are reported for C3v and Jahn-Teller distorted conformations of the methoxy radical CH3O. The Jahn-Teller distortion reduces the energy relative to the minimum energy for the C3v structure by -0.64 kcal/mol. Furthermore, the dynamic Jahn-Teller effect reduces the calculated spin-orbit splitting from 78 to 37 cm-1. An analysis of the Jahn-Teller energy surface yields the e mode vibrational frequencies (ν4 = 2314, ν5 = 1066, ν6 = 792 cm-1) and Coriolis coupling coefficients (ζ4 = 0.065, ζ5 = -0.152, and ζ6 = 0.186) for the ground state. The orbital g factor g0 = 0.647 was calculated and used to determine the components of the g tensor for free methoxy and matrix-trapped methoxy. For free methoxy, g∥ = 2.645 and g⊥ = 0; for the matrix-trapped radical, experimental data was used to calculate the splitting 1.7 kcal/mol of the methoxy energy level caused by its site environment. This splitting quenches g∥ to a value of 2.096.
- Publication:
-
Journal of Chemical Physics
- Pub Date:
- April 1982
- DOI:
- 10.1063/1.443491
- Bibcode:
- 1982JChPh..76.4144B
- Keywords:
-
- Atomic Structure;
- Jahn-Teller Effect;
- Many Body Problem;
- Methoxy Systems;
- Perturbation Theory;
- Spin-Orbit Interactions;
- Coupling Coefficients;
- Vibrational Spectra;
- Zeeman Effect;
- Atomic and Molecular Physics