Coherent Atomic Orbital Polarization Probes the Geometric Phase in Photodissociation of Polyatomic Molecules

TL;DR

This paper demonstrates how a geometric phase effect explains coherent atomic orbital polarization in ozone photodissociation, providing new physical insights into polyatomic molecular dynamics.

Contribution

It introduces a model revealing the role of a novel geometric phase manifestation in explaining previously unexplained polarization measurements in polyatomic molecules.

Findings

Geometric phase influences atomic orbital polarization in ozone dissociation.

The model explains experimental observations that lacked theoretical explanation.

Coherent polarization can be enhanced or canceled by the geometric phase.

Abstract

Quantum interference between multiple pathways in molecular photodissociation often results in angular momentum polarization of atomic products and this can give deep insight into fundamental physical processes. For dissociation of diatomic molecules the resulting orbital polarization is fully understood and consistent with quantum mechanical theory. For polyatomic molecules, however, coherent photofragment orbital polarization is frequently observed but so far has eluded theoretical explanation, and physical insight is lacking. Here we present a model of these effects for ozone photodissociation that reveals the importance of a novel manifestation of the geometric phase. We show this geometric phase effect permits the existence of coherent polarization in cases where it would otherwise vanish, and cancels it in some cases where it might otherwise exist. The model accounts for measurements in ozone that have hitherto defied explanation, and represents a step toward a deeper understanding of coherent electronic excitation in polyatomic molecules and a new role of the geometric phase.