Hydrazine Adsorption on Hexagonal Ice (0001): First‐Principles Investigations on Stability, Dynamics, and Chirality Changes

Hydrazine is a highly hazardous chemical and can be present in the atmosphere due to its usage in rocket fuels and propellant mixtures. Ice particles, present in polar stratospheric clouds, are common components of the natural atmosphere and can adsorb small organic molecules, such as hydrazine. We investigate the (0001) surface of hexagonal ice, acting as a phase boundary for the adsorption of hydrazine using density functional theory (DFT). Different types of position of hydrazine monomers and dimers on the ice surface were considered. We analyze the energetic and structural properties of these adsorbates utilizing static DFT calculations and Car–Parrinello molecular dynamics simulations. We study the interplay between molecule–molecule (N ₂ H ₄ –N ₂ H ₄ ) and molecule–substrate (N ₂ H ₄ –ice surface) interactions, in particular self‐aggregation of hydrazine in H‐bonded complexes. Molecular dynamics simulations enable to study the dynamics of the system, namely, reaction pathways for molecular rearrangements of N ₂ H ₄ monomers and dimers and the possible interconversion between the two hydrazine enantiomers on the ice (0001) surface.