J. Phys. IV France 114 (2004) 633
Reinvestigation of structural and magnetic properties of a cyano-bridged bimetallic compound: K 2Mn 3(H 2O) 6[ Mo(CN) 7] 2 6H 2OX.F. Le Goff1, R. Clérac1, 1, C. Coulon1 and B. Donnadieu2
1 Centre de Recherche Paul Pascal (CRPP), UPR CNRS 8641, 115 avenue du Dr. A. Schweitzer, 33600 Pessac, France
2 Laboratoire de Chimie de Coordination (LCC), UPR CNRS 8241, 205 route de Narbonne, 31077 Toulouse Cedex 4, France
In this communication, we reinvestigate the structural and magnetic properties of the title compound K 2Mn 3(H 2O) 6[ Mo(CN) 7] 6H 2O. We show that this material crystallises in the space group C2/c (monoclinic no.15), instead of C2 (monoclinic no.5) reported by J. Larianova et al. in J. Am. Chem. Soc., 121 (1999) 3349 - 3356. The C2/c and C2 unit cells are closely related. The presence of an inversion center in the C2/c unit cell implies the doubling of the c parameter in comparison to the C2 unit cell. Magnetic measurements show a transition from a paramagnetic state to a ferrimagnetic ordered state at 39 K, in agreement to neutron diffraction experiments. Key words. X-ray diffraction - Ferrimagnet - Heptacyanomolybdenate.
© EDP Sciences 2004