Intramolecular Antiferromagnetic Coupling in Supramolecular Grid Structures with Co2+ Metal Centers

Waldmann, Oliver; Hassmann, Jörg; M\", Paul; uller, ; Hanan, Garry S.; Volkmer, Dirk; Schubert, Ulrich S.; Lehn, Jean-Marie

Abstract:

The magnetization of novel supramolecular grid structures consisting of four bis(bipyridyl)- pyrimidine ligands and four Co21 ions was measured. We provide evidence for an antiferromagnetic coupling of the Co21 spins. Investigations of microcrystals, powders, and solutions with the mean distance of the grids varying from 20 to 160 Å showed that the coupling is solely of intramolecular origin and is not affected by long-range ordering. Thus, these grids form an almost ideal quantum spin system of four spins. This is further supported by low-temperature field-sweep measurements.

Year:

1997

Type of Publication:

Article

Journal:

Physical Review Letters

Volume:

78

Pages:

3390 – 3393