Experimental and Theoretical Studies of the N(2D) + H2 and D2 Reactions

TL;DR

This paper combines experimental measurements and theoretical calculations to study the reaction rates of N(2D) with H2 and D2 at low temperatures, providing insights into reaction dynamics and discrepancies between models.

Contribution

It presents new low-temperature rate constants measured experimentally and compares them with two advanced theoretical approaches, highlighting differences and challenges in modeling these reactions.

Findings

Rate constants measured down to 127 K.

Discrepancies observed between experimental and theoretical results.

Comparison of SQM and SC-Capture models discussed.

Abstract

This study reports the results of an experimental and theoretical investigation of the N(2D) + H2 and N(2D) + D2 reactions at room temperature and below. On the experimental side, a supersonic flow (Laval nozzle) reactor was employed to measure rate constants for these processes at temperatures as low as 127 K. N(2D) was produced indirectly by pulsed laser photolysis and these atoms were detected directly by pulsed laser induced fluorescence in the vacuum ultraviolet wavelength region. On the theoretical side, two different approaches were used to calculate rate constants for these reactions; a statistical quantum mechanical (SQM) method and a quasi-classical trajectory capture model including a semi-classical correction for tunneling (SC-Capture). This work is described in the context of previous studies, while the discrepancies between both experiment and theory, as well as between the theoretical results themselves are discussed.