Kinetics and Dynamics of the S(^1D_2) + H_2 \to SH + H Reaction at Very Low Temperatures and Collision Energies

TL;DR

This study investigates the reaction kinetics and dynamics of S(^1D_2) with H2 at very low temperatures, combining experimental measurements and quantum calculations to understand behavior near the cold energy regime.

Contribution

It provides new experimental data and quantum calculations for the S(^1D_2) + H2 reaction at unprecedented low temperatures and collision energies.

Findings

Rate coefficients measured down to 5.8 K

Cross sections obtained at collision energies as low as 0.68 meV

Results explained by partial wave contributions

Abstract

We report combined studies on the prototypical S(^1D_2) + H2 insertion reaction. Kinetics and crossed-beam experiments are performed in experimental conditions approaching the cold energy regime, yielding absolute rate coefficients down to 5.8 K and relative integral cross sections to collision energies as low as 0.68 meV. They are supported by quantum calculations on a potential energy surface treating long range interactions accurately. All results are consistent and the excitation function behavior is explained in terms of the cumulative contribution of various partial waves.