Synthesis and structural DFT studies of Ni(II) and Co(II) complexes with s-triazine-based di-compartmental ligand

Abstract

The two dinuclear complexes with octahedral metal centres, [Co2L(H2O)3Cl3]Cl (1) and [Ni2L(H2O)4Cl2]Cl2 (2), of the s-triazine-based di-compartmental ligand L were synthesized and characterized using single crystal X-ray diffraction (SC-XRD). The ligand L acts as a tridentate NNN-chelate with a pyrimidine-like coordinative behavior. The coordination of L was found to depend on the size of metal ion. Hirshfeld analysis indicated that the molecular packing of the studied complexes is controlled mainly by polar Cl⋯H and O⋯H contacts. The Cl⋯H interactions represent about one quarter of all the observed contacts in complexes 1 (25.4%) and 2 (31.0%), while the less important O⋯H interactions comprise 6.4 and 6.6% from the whole intermolecular interactions, respectively. The relative stability of the different conformers of L was investigated using different DFT methods and the different conversion reactions between them were analyzed using QST2 calculations.