SPIN DILUTION IN A FERROMAGNETIC CHAIN

We have systematically introduced spinless defects in the quasi-one-dimensional ferromegnetic system decamethylferrocenium tetracyanoethanide, [FeCp2*][TCNE]. The three-dimensional ordering temperature T(c) decreases rapidly with the concentration of spinless sites. The rate of decrease of T(c) with concentrate is in the order of the exchange spatial anisotropy (i.e., J(interchain)/J(intrachain)) of the parent system in accordance with long-standing theoretical predictions.