Long-Range Complex in the HC3N + CN Potential Energy Surface: Ab Initio Calculations and Intermolecular Potential

TL;DR

This study investigates the potential energy surface of the HC3N + CN reaction, identifying a van der Waals adduct and analyzing its properties through ab initio calculations and intermolecular potential modeling.

Contribution

It provides detailed ab initio characterization of the HC3N + CN interaction, including the adduct geometry and energy landscape, advancing understanding of this reaction's PES.

Findings

The adduct's energy is below that of the reactants.

A saddle point connects the adduct to an intermediate, also below reactant energy.

Intermolecular potential calculations show higher adduct energy than ab initio estimates.

Abstract

In this work we characterize an initial van der Waals adduct in the potential energy surface of reaction between cyanoacetylene HC3N and the cyano radical. The geometry of the CN-HC3N adduct has been optimized through calculations employing ab initio methods. Results show that the energy of the adduct lays below the reactants. Additionally, a saddle point that connects the adduct to an important intermediate of the PES has been localized, with energy below the reactants. Calculations of the intermolecular potential have been performed and results show that the energy of the van der Waals adduct is higher than estimated with the ab initio methods.