A novel paramagnetic (S = 1/2) copper dithiolene complex based on the tfadt ligand (tfadt: 3-trifluoromethylacrylonitrile-2,3-dithiolate) is prepared as its n-Bu4N+ salt and crystallized with [Ni(cyclam)](2+) into infinite, one-dimensional chains through CN...Ni interactions, avoiding any direct (antiferromagnetic) overlap between the dithiolene complexes. An unprecedented ferromagnetic interaction within the heterobimetallic chains between the S = 1/2 [Cu(tfadt)(2)](2-) and the S = 1 [Ni(cyclam)](2+) tectons is observed, despite the fact that the SOMOs of both (Cu(ffadt)(2)](2-) (with d(x2-y2) symmetry) and [Ni(cyclam)](2+) (with d(x2-y2) and d(z2) symmetry) have the same e(g) symmetry. The experimental exchange interaction deduced from the fit of the magnetic susceptibility (J(exp) kB = +5.0 K) was confirmed by theoretical calculations (J(calc)/k(B) = +7.3 K), and a rationale is given for the presence of an intrachain ferromagnetic interaction.