The ferromagnetic [Ln2Co6] heterometallic complexes.

Four 3d-4f heterometallic complexes with the formula, {[Ln2Co6(OH)4(L1)6(L2)8(CH3CN)2]·nCH2Cl2} (Ln = Dy (1), n = 0.5; Ho (2), n = 1; Gd (3), n = 1; Y (4), n = 1; HL1 = 6-chloro-2-pyridinol, HL2 = pivalic acid), were synthesized. Single-crystal X-ray diffraction analyses revealed that complexes 1-4 consisted of a [Ln2Co6] core, featuring a Ln-Ln edge-sharing double-trigonal-bipyramid configuration. The magnetic susceptibilities revealed ferromagnetic coupling within complexes 1 and 2, and complex 1 displayed slow relaxation of magnetization.