Merging Two Molecular Beams of ND$_3$ up to the Liouville Limit

TL;DR

This paper introduces a novel electrostatic guide that enables merging of ND$_3$ molecular beams at very low collision energies, facilitating the study of dipolar molecule interactions.

Contribution

The paper presents the design and implementation of a merged electrostatic guide optimized for ND$_3$-ND$_3$ and ND$_3$-NH$_3$ collisions, achieving minimal collision angles.

Findings

Guide successfully merges beams at 2° angle

Preliminary data on inelastic ND$_3$-ND$_3$ collisions

Optimized for low-energy dipolar collision studies

Abstract

In low-energy collisions between two dipolar molecules, the long-range dipole-dipole interaction plays an important role in the scattering dynamics. Merged beam configurations offer the lowest collision energies achievable, but they generally can not be applied to most dipole-dipole systems as the electrodes used to merge one beam would deflect the other. This paper covers the design and implementation of a merged electrostatic guide whose geometry was numerically optimized for ND$_3$-ND$_3$ and ND$_3$-NH$_3$ collisions. This device guides both beams simultaneously and makes them converge up to an effective collision angle of 2$\mathrm{^\circ}$, yielding the optimal compromise between spatial overlap and the lowest possible collision energy. We present preliminary data for inelastic ND$_3$-ND$_3$ collisions.