Molecular structure and EPR data of Dimeric Di-*-azide-bis[cyanide(N,N-diethylethylenediamine)]Copper(II) [Cu(N3)(NCO)di Eten]2

O.E. PIRO; E.E. CASTELLANO; J. ZUKERMAN-SCHPECTOR; C.A. DE SIMONE; D.M. MARTINO; C.A. STEREN

JOURNAL OF CHEMICAL CRYSTALLOGRAPHY

Año: 1997 vol. 27 p. 129 - 135

1074-1542

The title compound, [Cu(N3)(NCO)(CrHI6N2)]2, crystallizes in the space group P21/n, witha = 8.336(1), b = 17.405(3), c = 8.376(1) ,/~, 13 = 109.73(2) ~ and Z = 4. The molecules arearranged as centrosymmetric dimers in which two azide ligands bridge neighboring copperions in an asymmetric head-on fashion. The Cu(ll) ion is coordinated to five nitrogen atomswhich form a distorted tetragonal pyramid. At the pyramid base are the two N atoms of adiEten molecule [Cu-N = 2.00(1), 2.130(9) ,~,], an azide end atom [Cu-N = 1.99(1) .~] anda NCO group [Cu-N = 1.93(1) ,~]. At the pyramid apex is the other, inversion related, azideN atom in the dimer [Cu-N = 2.38(1) ,~]. This Cu-N contact links the monomers within adimer. Neighboring dimers are coupled by weak N-H...O contacts. Single crystal EPR data atX-band show that the pair of resonances expected for neighboring, magnetically nonequivalentsdimers, collapse into a single line, a signature of inter-dimers superexchange coupling. Theobserved crystal gyromagnetic tensor is used to disclose the electronic and magnetic structurearound Cu(II) ions.