JAHN-TELLER COUPLING IN THE METHOXY RADICAL: INSIGHTS INTO THE INFRARED SPECTRUM OF MOLECULES WITH VIBRONIC COUPLING

Johnson, Britta

Permalink

https://hdl.handle.net/2142/79219 Copy

Description

Title

JAHN-TELLER COUPLING IN THE METHOXY RADICAL: INSIGHTS INTO THE INFRARED SPECTRUM OF MOLECULES WITH VIBRONIC COUPLING

Author(s)

Johnson, Britta

Contributor(s)

Sibert, Edwin

Issue Date

23-Jun-15

Keyword(s)

Radicals

Abstract

hspace*{1cm} The ground $tilde{X}^2E$ vibrations of the methoxy radical have intrigued both experimentalists and theorists alike due to the presence of a conical intersection at the $C_{3v}$ molecular geometry. This conical intersection causes methoxy's vibrational spectrum to be strongly influenced by Jahn-Teller coupling which leads to large amplitude vibrations and extensive mixing of the two lowest electronic states. The spectrum is further complicated due to spin-orbit and Fermi couplings. The standard diabatic normal mode quantum numbers are poor labels due to this vibronic mixing. medskip hspace*{1cm} Using the potential energy force field and calculated spectra of the methoxy radical by Nagesh and Sibert$^1$ as a starting point, we look to develop a method for assigning states to a spectrum with vibronic coupling. We simplify the analysis by considering only the lowest two {em e} modes of methoxy (the rock and the bend). When we include first-order Jahn-Teller coupling between these two modes in a new zero-order Hamiltonian, we are able to use an expanded version of the linear Jahn-Teller quantum numbers to assign the states.$^2$ This zeroth order representation is nontrivial; therefore, we study the properties of its eigenstates using correlation diagrams with respect to the strength of the Jahn-Teller coupling constant. medskip begin{list}{}{}item[$^1$] Nagesh, J.; Sibert, E.~L. {em J. Phys. Chem. A} {bf 2012}, {em 116}, 3846--3855. item[$^2$] Barckholtz, T.~A.; Miller, T.~A. {em Int. Revs. in Phys. Chem.} {bf 1998}, {em 17}, 435--524. end{list}

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

English

Permalink

http://hdl.handle.net/2142/79219

Owning Collections