The structures and characterization are described of complexes that exhibit an out-of-phase AC magnetic susceptibility Chim″. The dodecanuclear complexes [Mn12O12(O2CR)16(H 2O)4]2 contain 8MnIII,4MnIV or MnII,7MnIII, 4MnIV and possess ground state spins of S = 9 or 10 (z = O) or S = 19/2 (z = -1). The distorted-cubane complexes [Mn4O3X(O2CR)3(dbm)3] contain 3MnIII,MnIV and have been prepared with a variety of X groups; in every case, the ground state is S = 9/2. The anion [Mn11O10X6(O2CPh) 11(H2O)4]2- (9MnIII, 2MnIV; X = NCO-, N3-) contains two [Mn4O3X] distorted-cubanes linked by a [Mn3O4]+ unit; the ground state is S = 5. The cation [V4O2(O2CEt)7O)Py)2] + (4VIII) has a [V4O2]8+ butterfly core and a S = 3 ground state. All these complexes exhibit out-of-phase AC magnetic susceptibility signals at low temperatures (<8 K). These signals are indicative of slow relaxation of the magnetization, unable to keep in phase with the oscillating AC magnetic field, and are taken as evidence for single-molecule magnetism. The origin of the barrier to relaxation is discussed.
|Number of pages||13|
|Journal||Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals|
|Publication status||Published - 1997 Jan 1|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics