Effect of confinement and external mechanical force on the cleavage of the bond in a diatomic molecule

Mechanochemical synthesis has gained much attention owing to its environment-friendly nature. The application of mechanical force on the reactants changes the reactivity of the chemical systems and the reactivity of the chemical entities can be changed by altering its surrounding, like encapsulating the chemical entities inside a cavity. The effect of confinement and mechanical stretching force on the nature of the bond in the diatomic systems has been extensively studied using theoretical models. The diatomic systems that have been considered are F-2, H-2, O-2, N-2, ClBr, NaCl, CO, LiF and HCl and the confinement being used is that of fullerene cage C-60. It has been found that the confinement strengthens the diatomic bond for ClBr, NaCl, N-2 and H-2 systems whereas for some other systems, the bond strength decreases. The possible reason behind such observation has been explored with the help of Natural Bond Orbital (NBO) analysis, Atoms in Molecules (AIM) analysis and Energy Decomposition Analysis (EDA). The reactivity change with respect to the external mechanical stretching force has been studied and the presence of non-covalent interaction (NCI) is visualised through NCI plots. The dynamics of the systems have also been explored using Atom Centred Density Matrix propagation (ADMP) simulation.

Automated summary

Mechanochemical synthesis has become popular due to its eco-friendly nature. The reactivity of chemical systems can be altered by applying mechanical force and changing the surrounding environment. The study focuses on the effect of confinement and mechanical stretching force on diatomic systems, such as F-2, H-2, O-2, N-2, ClBr, NaCl, CO, LiF, and HCl, using fullerene cage C-60 as confinement. The bond strength of the diatomic systems varies, with some systems showing an increase in bond strength under confinement while others show a decrease. The analysis of Natural Bond Orbital (NBO), Atoms in Molecules (AIM), and Energy Decomposition Analysis (EDA) provides insights into the reasons behind such variations.