Cyanamide group, a three atom ?-system, is a poor ?- acceptor system but is a good ?-donor of nitril ligands. The attachment of a phenyl ring to the cynamide group adds an extra dimensio not present in azido or thiocyanate ligands.An extensive ? conjugation between the cynamide grou and the phenyl ring provids an energeticaly favorable means by which a metal ion can couple into a conjugated organic ? system. In this thesis, at first, four ligands of phenylcynamide derivatives like (4-NO 2 pcyd), (4-Br pcyd), (4-F pcyd) and (4-Cl pcyd) where pcyd= phenyl cyanamide , on the base of thiourea route, have been prepared and characterized by elemental analysis, FT-IR and UV-Vis. Then, six coordinate complexes of [Ni(4-X pcyd) 2 (H2O) 4 ] in which X= F, Cl, Br, NO 2 prepaerd y the reaction of [Ni(oAc) 2 (H 2 O) 4 ] whit appropriate of henycynamide ligands. Each of the complexes has een characterized y IR and UV-Vis spectroscopic date. Due to biological activities and chemical importane of o -phenanthroline and phenyl cyanamide derivatives, we have synthesized and reported crystal structure of cis -[Ni(phen) 2 (4-NO 2 pcyd) 2 ] which Ni(II) in this complex has octahedral structure . Preliminary pharmacological tests have showed [Mn(phen) 2 (4-NO 2 pcyd) 2 ], exhibited definite inhibition activites against human ovary tumor. A fundamental understanding of polynuclear transition metal is of key importance to design of molecular devices such as low impedance molecular wires, molecular switches, as well as the creation of novel materials with useful magnetic or optical properties. Such devices could find application in a variety of areas such as nanoscale electronics, bioilogical probes, magnetic shield and video diplay. Finally, crystal structure deremination of complex [Cd(4-NO 2 pcyd) 2 (DMF) 2 ] , Due to polynuclear transition metal importance to design of molecular devices such as low impedance molecular wires , molecular switches … etc, has bee performed. This complex has a polynuclear structure and ( 4-NO 2 pcyd) ligand has been dridged whitin complex. The crystal structure is showed bridging phenylcyanamide coordination with Cd(II) in octahedral structure.