Abstract

Omar Hamad Shehab AL- Obaidi, Taghreed M.Musa, Mahmod N.Al-jibouri

The complexes of a new pentadentate acyclic ligand derived from 1,2-diamino benzene and 2,6- diacetylpyridine with vanadium(IV), Cr(III), Mn(II), Fe(III), Co(II), Ni(II), and Cu(II) have been synthesized. Metal to ligand ratio in all complexes has been found to be 1:1. The polydentate ligand behaves as N5 system upon linkage with Cr (III), Fe (III), Mn(II), Co(II), and Cu(II) ions. All the complexes have been assigned octahedral stereo chemistry, while VO (IV) complex was square pyramid. The thermodynamic parameters such as �??G*, �??H* and �??S* are calculated from the curve of logKs verse temperature. It is found that Ni (Π) and Cu (II) are the most stable complexes from the data of formation constant and Gibbs free energy.