Synthesis, crystal structure and magnetic properties of catena-poly[(2,2′-bipyridylcopper)-di-μ-thiocyanato] and bis(2,2′-bipyridyl)thiocyanatocopper(II) perchlorate
1999; Elsevier BV; Volume: 286; Issue: 2 Linguagem: Inglês
10.1016/s0020-1693(98)00397-1
ISSN1873-3255
AutoresC. Díaz, Joan Ribas, N. Sanz, Xavier Soláns, Mercè Font‐Bardía,
Tópico(s)Lanthanide and Transition Metal Complexes
ResumoThe reaction of ethanolic solutions of CuX2 (X=NO3 −, ClO4 −), with bidentate amine, 2,2′-bipyridyl (bipy) and ammonium thiocyanate, leads to the high-yield formation of {catena-[Cu(bipy)(μN,S-NCS)2]} (1) and [Cu(NCS)(bipy)2]ClO4 · 1/2CH3CN (2). The crystal structure of 1 and 2 were determined. Complex 1 crystallises in the monoclinic system, space group C2/c with a=8.125(4) Å, b=15.557(6) Å, c=10.536(3) Å, β=95.32(3)° and Z=4. The crystal structure consists of neutral Cu(NCS)2(bipy) units which are bridged by sulfur atoms of the thiocyanate groups to yield a 1D chain. Complex 2 crystallises in the monoclinic system, space group C2/c with a=12.694(4) Å, b=25.007(11) Å, c=15.479(11) Å, β=106.85(4)° and Z=8. The crystal structure consists of a [Cu(NCS)(bipy)2]+ cation, ClO4 − anion and CH3CN. The cations show a quasi-trigonal bipyramidal coordination. A variable temperature magnetic susceptibility study was performed on 1 at a temperature range of 2–300 K. The compound shows a very weak antiferromagnetic coupling (J=−0.13 cm−1) and the magnetic susceptibility data were analysed by the expression for the magnetic susceptibility of isotropically coupled S=1/2 ions in antiferromagnetic chains. The single crystal EPR spectra of 2 presents rhombic g values and the direction of the highest g value lies in the equatorial plane near the Cu–Neq direction; therefore, this is a distorted trigonal bipyramidal structure.
Referência(s)