Steric paths in confined hydrogen molecule inside carbon nanorings and fullerenes

Steric molecular graph is introduced as gradient paths connecting critical points responsible for depletion of charge density due to steric deformation density. Since steric repulsion dominates intermolecular interaction in confined systems, surrounded and encapsulated hydrogen molecule inside carbon nanorings and fullerenes are considered as confined systems, respectively. It is shown that structure of steric graph is consistent with the confinement dimensionality, i.e., ring-and cage-type steric graph appear for two-and three-dimensional confinements, respectively.