An insight to the role of perchlorate counter ions and different non-covalent interactions in the solid state structures of mono-anionic malonic acid bridged trinuclear mixed valence cationic complexes of cobalt with tetradentate N2O2 donor ligands

Two linear mixed-valence trinuclear centrosymmetric cobalt(III)-cobalt(II)-cobalt(III) complexes, [CoII{(mu-L1) (mu-OOCCH2COOH)CoIII(DMF)}2](ClO4)2.2DMSO (1) and [CoII{(mu-L2)(mu-OOCCH2COOH)CoIII(DMF)}2] (ClO4)2.2DMSO (2) have been synthesized using tetradentate N2O2 donor 'reduced Schiff base' ligands, H2L1 (2,2-dimethyl-1,3-propanediyl)bis(iminomethylene)bis(phenol) and H2L2 (2,2-dimethyl-1,3-propanediyl)bis (iminomethylene)bis(4-chlorophenol), and malonic acid as anionic co-ligand. The complexes have been char-acterized by spectroscopic measurements and their solid state structures have been determined by single crystal X-ray diffraction analysis. Some supra-molecular assemblies observed in the solid state structures of both com-plexes have been analysed using DFT calculations, in particular CH3...pi and Cl...Cl interactions. QTAIM and NCI Plot computational tools have been used to characterize the interactions.