A new dichloro(1,10-phenanthroline)(1,2,4-triazole-3-carboxylic-acid)copper(II) was synthesized, and the most stable optimized structure was determined using the B3LYP/LANL2DZ basis set, followed by FTIR and NMR characterization. The molecular geometric structure analysis and vibrational frequencies of the Cu(II) complex were calculated by using density functional theory calculations in the ground state. Metal-ligand and intra-ligand vibrations were investigated using vibrational analysis, and the obtained computational values were compared with the experimental values. The ProTox-II webserver was utilized for toxicological evaluation of the organism and organ, as well as molecular mechanisms of toxicity evidenced by the median lethal dose (LD50). SwissADME prediction was performed ADMET properties. Reduced density gradient (RDG) analysis is employed to study the weak interactions within the molecule. The nature of the chemical bonds in the [Cu(phen)(TCA)(2)Cl-2] complex is investigated using electron localization function (ELF) analysis. MEPs, HOMO, LUMO, global reactivity descriptors, and Fukui functions are performed to study the chemical reactivity of the compound. Molecular docking studies are performed to predict the antibacterial, antidepressant, and anti-anxiety active site of the complex. Cu(phen)(TCA)(2)Cl-2 was defined and used to evaluate the antibacterial properties of this Cu(II) complex against B. subtilis.