The crystals of a (formula presented) cluster (formula presented) are mosaic, at least from the magnetic point of view, involving two kinds of molecules with different relaxation rates. The ratios of the two components in the crystals are strongly batch dependent. We characterize the two by comparing the magnetic properties of two batches in which the ratios are very different. The angular dependence of the magnetic properties indicates that the magnetic easy axis of the slow relaxation molecule is parallel to the molecular axis, while that of the fast relaxation (FR) molecule is tilted by (formula presented) The high-frequency electron paramagnetic resonance for the FR molecule supports the tilted easy axis and suggests an anisotropy even in its hard plane. The x-ray analyses demonstrate that the FR molecule involves a (formula presented) site with an unusual distortion.
|Number of pages||12|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2002|