Computational investigation on the thermodynamics of H2CO + NH2 NH2CHO + H on interstellar water ice surfaces

TL;DR

This study investigates the thermodynamics of formamide formation from NH2 and H2CO on interstellar ice surfaces using theoretical methods, providing insights into astrochemical processes relevant to prebiotic chemistry.

Contribution

It offers a novel theoretical analysis of the formation pathway of formamide on icy dust grains using DFT calculations with both cluster and periodic models.

Findings

Thermodynamics of formamide formation on ice surfaces characterized.

Different DFT functionals used to ensure accurate energy calculations.

Insights into astrochemical formation pathways of prebiotic molecules.

Abstract

Formamide has a key role in prebiotic chemistry as it is the simplest molecule containing the four most important atoms from a biological point of view: hydrogen, carbon, nitrogen and oxygen. Due to its importance, the formation of this molecule has been studied and different pathways have been considered both in gas-phase and on ices of dust grains since it was first detected. In the present work, the thermodynamics of the formation route of formamide starting from NH2 and H2CO, a reaction channel proposed to occur in the gas phase, has been theoretically investigated in the scenario taking place on icy dust grains modelled by both a cluster and a periodic approach. Different DFT functionals have been employed to obtain accurate energy values for the mechanistic steps involved in the reaction.