A comprehensive density functional theory (DFT/B3LYP method) investigation was done to study the generation, optimized topologies, bonding, reactivity, stability, distortions and enhancement of antimicrobial potential of a number of organic–inorganic hybrid complexes of zirconium (IV). Zirconium (IV) complexes having the general formulae ZrL(Cl)2 and Zr(L)2 were prepared by the reaction of zirconium tetrachloride with dipotassium salts of sterically constrained oximes of heterocyclic β‐diketones in different stoichiometric ratios in refluxing anhydrous THF. Plausible topologies of these complexes were suggested with the aid of physico‐chemical and spectral studies. The optimized topologies of the complexs of the types ZrL(Cl)2 and Zr(L)2 were given by comprehensive DFT investigation. The molecular orbitals, molecular electrostatic potential, chemical reactivity, energy optimization, stability and distortions of these newly generated complexes were studied by DFT. These complexes were screened against bacterial isolate E. Coli and fungal isolates viz. A. Niger and T. Reesei. The chemical reactivity of these complexes is corroborated by small energy gap. Few principal quantum chemical descriptors were correlated with the enhancement of antimicrobial potential of these sterically constrained complexes of zirconium (IV). The presence of ‐CH2CH3, ‐C6H5 and –C6H4Cl (p) groups in complexes of the types ZrL(Cl)2 and Zr(L)2 provides an opportunity to examine the effect on optimized energy, stability and distortions of optimized topologies.