Homo- and Heteroligand Copper(II) Complexes with Some Aromatic Acid Hydrazides and L-Histidine

― The composition and stability constants of homo- and heteroligand copper(II) complexes with benzoic acid, p -methoxybenzoic acid, or o -hydroxybenzoic acid hydrazide and L -histidine have been determined by spectrophotometry and mathematical modeling methods in aqueous solution with 0.1 M KNO 3 as background at 25.0°C. Structural features of some complexes formed in binary and ternary systems have been determined using IR spectroscopy and quantum-chemical calculations.