Structures and physical properties of nickel complexes with TTF-type ligands

New nickel complexes with ethylenedioxy-substituted TTF ligands, (R 4 N) n [Ni(eodt) 2 ] [R = Me, n = 2: (1); R = Bu, n = 1: (2); n = 0: (3)], were prepared. The tetra-n-butylammonium complexes with 1:1 composition showed Curie constants corresponding to s = 1/2 and relative large and anisotropic g-values by magnetic measurements, suggesting the importance (or contribution) of the nickel 3d orbital. The electrical resistivity measurement performed on the compressed pellet of the neutral complex, [Ni(eodt) 2 ] showed metallic behaviour down to ca. 120 K, which is consistent with the results of electron spin resonance experiments.