An investigation of z-in distortion in mononuclear Cu(II) complex with terpyridine ligands, [Cu(terpy)2](PF6)2

The first crystal structure of [Cu(terpy)(2)](PF6)(2), where terpy=2,2':6,2'-terpyridine is reported Green Crystals of [Cu(terpy)(2)](PF6)(2) were grown by ether diffusion into an acetonitrile solution of the complex. Crystal structure of this complex is tetragonal (space group: P (4) over bar 2(1c)) with a = 8.8916(3), c = 20.0214(13)angstrom, and z = 2. The structure was refined by using 1828 independent reflections with I > 2 sigma(I) to a R factor of 0.0809. The terpy ligands are tridentate and linked to the Cu(II) via three N atoms. The CuN6 entities have compressed octahedral geometry with the shortest Cu-N bonds that form the. axial positions. This complex represents z-in distortion at 293K and has a D-2d point group. The effective magnetic moment (mu(eff)) of [Cu(terpy)(2)](PF6)(2) Was measured to be 1.95BM by Evans method. Cyclic voltammetry experiment of the complex shows that the Cu(II/I) couple is quasi-reversible.