Self-assembled H-bonded supramolecular interactions in monomeric complex [Mg(H2O)6].L2.2bipy.H2O; [LH = 2-amino-5-nitrobenzoic acid, bipy = 4,4′-bipyridine]]]]: Joint theoretical calculations and Hirshfeld surface analysis

The prepared monomeric H-bonded complex [Mg(H2O)6].L2.2bipy.H2O I [LH = 2-amino-5-nitrobenzoic acid, bipy = 4,4′-bipyridine], has been characterized by single-crystal X-ray crystallography, IR spectroscopy, elemental analysis, and thermal stability. This complex has been solved crystallographically in the monoclinic centrosymmetric space group (P21/n). In the molecular structure, the Mg2+ ion is connecting with six water molecules through coordination whereas L, bipy, and one lattice water are present as counter atoms. The L is behaving as a counter anion and the overall charge of this H-bonded complex is stabilized by [Mg(H2O)6]2+cationic unit. The stability of I is attained due to collective coordination and H-bonding interactions which are responsible for organizing it into a supramolecular 2D motif. Hirshfeld surface analysis has been applied to scrutinize supramolecular H-bonding interactions as well as short or weak contacts and then compared the results with single-crystal X-ray data. The fingerprint plots demonstrate that the huge number of weak non-bonding interactions as compare to strong contacts is important for stabilizing the crystal packing. DFT calculations demonstrated that the thermodynamic stabilization of I may be attributed to the existence of inter-and intramolecular hydrogen interaction. NBO–Second-order perturbation theory analysis, displayed detraction in positive charge on Mg2+ ion upon coordination with surrounding water molecules.