Issue 19, 2012

Stereodynamics of multistate roaming

Abstract

We present a molecular level description of NO3 → NO + O2 photodissociation for both of the experimentally observed reaction pathways using the results of ion imaging experiments and recent theoretical studies. Vector correlation and Λ doublet propensity measurements have been performed on state-selected NO fragments in order to further characterize the stereodynamics of this reaction. Previous measurements (Grubb et al., Science, 2012, 1075–1078) of relative Λ doublet propensities along with ab initio calculations revealed that both pathways arise from roaming-type mechanisms, but each pathway arises from roaming on a different electronic potential. This model, however, assumes that NO3 dissociation takes place in the molecular plane. In the present paper, we have confirmed this assumption through speed-dependent vector correlation measurements. Strong perpendicular correlations between the velocity vector v and the angular momentum vector j are observed in the NO fragment originating from both pathways, in agreement with a constrained planar dissociation. These results are discussed in light of the absence of vector correlations in other roaming systems, which have previously been characterized by an unconstrained intra-molecular abstraction. We show that geometrical constraints should in fact be quite prevalent in roaming dynamics, and are analogous to the geometrical constraints of the corresponding bimolecular abstraction reaction.

Graphical abstract: Stereodynamics of multistate roaming

Article information

Article type
Paper
Submitted
23 Jan 2012
Accepted
13 Mar 2012
First published
13 Mar 2012

Phys. Chem. Chem. Phys., 2012,14, 6733-6740

Stereodynamics of multistate roaming

M. P. Grubb, M. L. Warter and S. W. North, Phys. Chem. Chem. Phys., 2012, 14, 6733 DOI: 10.1039/C2CP40235A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements