Two new Cull linear trinuclear Schiff base complexes, [Cu-3(L)(2)(CH3COO)(2)] (1) and [Cu-3(L)(2)(CF3COO)(2)] (2), have been prepared using a symmetrical Schiff base ligand H2L [where H2L = N,N'-bis(2-hydroxyacetophenone)propylenediimine]. Both of the complexes have been characterized by elemental analyses, Fourier transform IR, UV/vis, and electron paramagnetic resonance spectroscopy. Single-crystal X-ray structures show that the adjacent Cull ions are linked by double phenoxo bridges and a mu(2)-eta(1):eta(1) carboxylato bridge. In each complex, the central copper atom is located in an inversion center with distorted octahedral coordination geometry, while the terminal copper atoms have square-pyramidal geometry. Cryomagnetic susceptibility measurements over a wide range of temperature exhibit a distinct antiferromagnetic interaction of J = -36.5 and -72.3 cm(-1) for 1 and 2, respectively. Density functional theory calculations (B3LYP functional) and continuous-shape measurement (CShM) studies have been performed on the trinuclear unit to provide a qualitative theoretical interpretation of the antiferromagnetic behavior shown by the complexes.
Synthesis of Two New Linear Trinuclear CuII Complexes: Mechanism of Magnetic Coupling through Hybrid B3LYP Functional and CShM Studies / S., Thakurta; J., Chakraborty; G., Rosair; J., Tercero; M. S., EL FALLAH; Garribba, Eugenio; S., Mitra. - In: INORGANIC CHEMISTRY. - ISSN 0020-1669. - 47:(2008), pp. 6227-6235. [10.1021/ic8001459]