Theoretical Distribution of the Ammonia Binding Energy at Interstellar Icy Grains: A New Computational Framework.

ABSTRACT: The binding energies (BE) of molecules on the interstellar grains are crucial in the chemical evolution of the interstellar medium (ISM). Both temperature-programmed desorption (TPD) laboratory experiments and quantum chemistry computations have often provided, so far, only single values of the BE for each molecule. This is a severe limitation, as the ices enveloping the grain mantles are structurally amorphous, giving rise to a manifold of possible adsorption sites, each with different BEs. However, the amorphous ice nature prevents the knowledge of structural details, hindering the development of a common accepted atomistic icy model. In this work, we propose a computational framework that closely mimics the formation of the interstellar grain mantle through a water by water accretion. O

SUBMITTER: Tinacci L 

PROVIDER: S-EPMC9208021 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature