New Insights into Adsorption Behaviour of NH3 Molecules on Small (SiO2)n (n=2–7) Clusters Through Systematic Analysis of Structural and Topological Properties

Abstract

The adsorption of NH3 molecules on (SiO2)n (n = 2–7) clusters was explored using various theoretical methods. The stable structures, interaction energies, and bonding properties for the various methods were evaluated in detail. Reactivity analysis and optimization results showed that a single NH3 molecule preferentially adheres to the Si atom at the edge of the clusters. It was also observed that the energy gap and hardness of the complexes decreased with an increase in the number of NH3 molecules. Topological, electron localization function, and atoms-in-molecules analyses were performed to investigate the bonding characteristics of these complexes. In addition, the results of this study were compared with those obtained for a similar system (H2O molecules adsorbed onto SiO2 clusters), and the similarities and differences between the two systems were discussed.