Magnetic Nature of the Cr-Ln Interactions in [CrLn] Clusters with Slow Magnetic Relaxation.

Two 3-4 hetero-metal pentanuclear complexes with the formula {[CrLnL(OH)(HO)]EtNH} [Ln=Tb (), Dy (); HL=pivalic acid, EtN=triethylamine] have been produced. The metal core of each cluster is made up of a trigonal bipyramid with three Ln ions (plane) and two Cr ions (above and below) held together by six -OH bridges. Also reported with this series is the diamagnetic Cr-Y analogue ().

The ferromagnetic [LnCo] heterometallic complexes.

Four 3d-4f heterometallic complexes with the formula, {[LnCo(OH)(L)(L)(CHCN)]·nCHCl} (Ln = Dy (1), n = 0.5; Ho (2), n = 1; Gd (3), n = 1; Y (4), n = 1; HL = 6-chloro-2-pyridinol, HL = pivalic acid), were synthesized. Single-crystal X-ray diffraction analyses revealed that complexes 1-4 consisted of a [LnCo] core, featuring a Ln-Ln edge-sharing double-trigonal-bipyramid configuration.