Portal de Periódicos da CAPES

Crystal structure, magnetic properties and orbital interactions of the binuclear fumarato-bridged bis[((N-(2-diethylamino)ethyl)-salicylidenaminato)copper(II)] complex

1993; Elsevier BV; Volume: 214; Issue: 1-2 Linguagem: Inglês

10.1016/s0020-1693(00)87537-4

1873-3255

Constantinos E. Xanthopoulos, Michael P. Sigalas, G.A. Katsoulos, Constantinos A. Tsipis, Aris Terzis, A. Hountas,

Metal-Catalyzed Oxygenation Mechanisms

The title compound of formula [Cu2(SalNEt2)2(C4H2O4)], where SalNEt2=N-(2-(diethylamino)ethyl)- salicylidenaminate, has been synthesized and its structure solved at room temperature. It crystallizes in the monoclinic system, space group P21/c, with a=10.463(2), b=16.048(2), c=9.434(1) Å, β=106.91(1)° and Z=2. In the molecular structure of this centrosymmetric compound the two equivalent copper(II) ions are bridged by the fumarato ligand coordinated in an amphimonodentate mode. The local geometry around both copper(II) ions is approximately square planar. Magnetic susceptibility data for the complex as a function of temperature show weak exchange interactions. The fitting of these data to the HDVV (Ĥ=−2JŜ1Ŝ2), S1=S2=1/2 spin exchange model, yields a 2J value of −1.8 cm−1. An orbital interpretation of the observed weak antiferromagnetic interactions is presented based on the results of extended Hückel calculations on a model compound.