New theoretical method for calculating the radiative association cross section of a triatomic molecule: Application to N2-H-

TL;DR

This paper introduces a new theoretical approach for calculating radiative association cross sections of triatomic molecules, applied specifically to N2H- to assess its interstellar presence and potential as a tracer.

Contribution

A novel time-independent method adapted from photodissociation techniques for precise calculation of radiative association in triatomic molecules.

Findings

Calculated cross sections reveal features relevant to interstellar chemistry.

Rate coefficient at 10 K suggests N2H- could exist in space.

Method provides accurate bound state energies and wave functions.

Abstract

We present a new theoretical method to treat the atom diatom radiative association within a time independent approach. This method is an adaptation of the driven equations method developed for photodissociation. The bound states energies and wave functions of the molecule are calculated exactly and used to propagate the overlap with the initial scattering wave function. In the second part of this paper, this approach is applied to the radiative association of the N2H- anion. The main features of the radiative association cross sections are analysed and the magnitude of the calculated rate coefficient at 10 Kelvin is used to discuss the existence of the N2H- in the interstellar medium which could be used as a tracer of both N2 and H-.