Spectroscopic characterization, DFT modeling and antimicrobial studies of some novel nanoparticles mixed ligand complexes of NS bidentate ligand in presence of 2,2′-bipyridine

•Synthesis of new six complexes of Cr(III), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) with L in presence of Bipy.•Characterization of L, Bipy and their metal complexes with different techniques.•Optimized geometries for the compounds using DFT.•Evaluation of the antimicrobial activities for the compounds against some Gram-positive, Gram-negative bacteria and fungi.