Dynamic and Static Behaviors of N–Z–N σ(3c–4e) (Z = S, Se, and Te) Interactions: Atoms-in-Molecules Dual Functional Analysis with High-Resolution X-ray Diffraction Determination of Electron Densities for 2-(2-Pyridylimino)-2H-1,2,4-thiadiazolo[2,3-a]pyridine

The structure of 2-(2-pyridylimino)-2H-1,2,4-thiadiazolo[2,3-a]pyridine (NSN) indicates that the molecule has a planar geometry with a linear N···S···N linkage, creating a tetracyclic structure of the formal C(2v) symmetry. To clarify the nature of the NSN σ(3c-4e) bonding, together with the related NSeN and NTeN, the dynamic and static behaviors are investigated by applying atoms-in-molecules (AIM) dual functional analysis to both the fully...