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Nonadiabatic effects in substitutional isomers of Jahn-Teller molecules: the strange case of hydroxymethoxy
Joseph Dillon1, David R Yarkony
1Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA. jdillon5@jhu.edu
Abstract:
The effects of nonadiabatic interactions attributable to a seam of conical intersections on the electronic structure of the 1,2(2)A states of hydroxymethoxy (HO)CH(2)O is explored. Illuminating comparisons are made between hydroxymethoxy and ethoxy and isopropoxy, all of which can be thought of as substitutional isomers of the methoxy radical. Surprisingly, the potential energy surfaces and conical topographies for hydroxymethoxy are shown to be dramatically different from those evidenced in ethoxy or isopropoxy radicals, dissimilarities traced to the hydroxyl group. Also considered in this study was the feasibility of representing the coupled 1,2(2)A adiabatic electronic states of hydroxymethoxy within the vibronic coupling approximation using a quasi-diabatic Hamiltonian and subsequently using that representation to simulate the photoelectron spectrum of the hydroxymethoxide anion. Complications attributable to the torsional motion of the hydroxyl hydrogen are analyzed.
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