Tris(pyridin-2-yl)phosphoric triamide, as a metal complex and purely organic pseudopolymorphs, and the role of solvent/hydrate and substituent in the formation of the crystal packing features, along with an improved model of the MOF structure of Cu(ii)O6 are investigated.

Crystal structures of six new phosphoramides with the main parts [C(O)NH]P(O)[N]2 and [NH]2P(O)[N] were determined by single crystal X‐ray diffraction and characterized by spectroscopic methods (FT‐IR and 1H, 13C, 31P NMR). X‐ray crystallography data manifest that the hydrogen bond interactions N−H…O (in all structures) accompanied by some contacts such as C−H…X (X=π, O, F and Cl) and π…π dominate the molecular architectures. Some non‐classical interactions such as Cl…π are also found in feature packing of some studied structures. A detailed investigation of these intermolecular interactions in order to illustrate the importance of non‐classical interactions in construction of molecular assemblies is presented by Hirshfeld surface (HS) analysis reflected the most important van der Waals (vdW) contributions and “Quantum Theory Atom In Molecule” (QTAIM) method especially in term of energetic feature. Hirshfeld surface analysis reveals that the prevalent interactions are of the type O…H for all structures coupled with some other short contacts such as C…C and H…F recognized by red spots on Hirshfeld surfaces and enrichment ratios (E) larger than unity (E > 1). These results are confirmed by AIM method classifying the hydrogen bond interactions N−H…O as moderate non‐covalent closed‐shell interactions and the remaining interactions above‐mentioned as vdW closed‐shell interactions in the studies phosphoric triamides. Such study to categorize the popular hydrogen bond interactions N−H…O in phosphoric triamides and the weak interactions in their molecular packing are used for the first time.