Long-range ferromagnetic dipolar ordering of high-spin molecular clusters.
We report the first example of a transition to long-range magnetic order in a purely dipolarly interacting molecular magnet. For the magnetic cluster compound Mn6O4Br4(Et2dbm)6, the anisotropy experienced by the total spin S = 12 of each cluster is so small that spin-lattice relaxation remains fast down to the lowest temperatures, thus enabling dipolar order to occur within experimental times at T(c) = 0.16 K. In high magnetic fields, the relaxation rate becomes drastically reduced and the interplay between nuclear- and electron-spin lattice relaxation is revealed.
Morello
A
A
Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
Mettes
F L
FL
Luis
F
F
Fernández
J F
JF
Krzystek
J
J
Aromí
G
G
Christou
G
G
de Jongh
L J
LJ