THE CHROMATE ION AS A LIGAND - PHYSICOCHEMICAL STUDIES OF NICKEL(II) CHROMATE COMPLEXES WITH 2,2'-BIPYRIDINE

The preparation of two novel nickel chromate complexes with 2,2'-bipyr idine is described. The results of thermal, spectral, magnetic and sca nning microscopic studies are analyzed. The data show that the complex es are monomers with pseudooctahedral arrangement around the nickel io n. The coordination of the chromate ion has been found in one of the c omplexes. The TG-DTC-DTA data show that the thermal decomposition of t he complexes occurs in two and three stages in air and four stages in He atmosphere. The decomposition of the complexes has been discussed a nd compared to that known for other metal chromate complexes with bpy. (C) 1998 Elsevier Science B.V.