A novel crossed-molecular-beam experiment for investigating reactions of state- and conformationally selected strong-field-seeking molecules

TL;DR

This paper introduces a new experimental setup using an electrostatic deflector in a crossed-molecular-beam system to study how the quantum state and geometry of strong-field-seeking molecules influence reaction pathways, demonstrated with neon and OCS reactions.

Contribution

It presents a novel experimental method for investigating reactions of strong-field-seeking molecules with state- and geometry-specific control, expanding capabilities beyond weak-field-seeking studies.

Findings

Branching ratio varies with initial rotational state of OCS

Reactions show state-dependent pathways in chemi-ionisation

New setup enables detailed single-collision reaction analysis

Abstract

The structure and quantum state of the reactants have a profound impact on the kinetics and dynamics of chemical reactions. Over the past years, significant advances have been made in the control and manipulation of molecules with external electric and magnetic fields in molecular-beam experiments for investigations of their state-, structure- and energy-specific chemical reactivity. Whereas studies for neutrals have so far mainly focused on weak-field-seeking species, we report here progress towards investigating reactions of strong-field-seeking molecules by introducing a novel crossed-molecular-beam experiment featuring an electrostatic deflector. The new setup enables the characterisation of state- and geometry-specific effects in reactions under single-collision conditions. As a proof of principle, we present results on the chemi-ionisation reaction of metastable neon atoms with rotationally state-selected carbonyl sulfide (OCS) molecules and show that the branching ratio between the Penning and dissociative ionisation pathways strongly depends on the initial rotational state of OCS.