Magnetic percolation in CN-bridged ferrimagnetic coordination polymers

Abstract

A series of diluted molecular magnets {[Mn^II(H₂O)₂]₂[M^IV(CN)₈]·4H₂O}_n (M = Nb/Mo) exhibiting a ferrimagnetic phase have been synthesized and investigated to demonstrate the first example of site percolation in magnetic coordination polymers. It is the first case of a magnetic percolation study with selective site substitution, where magnetic ions of only one type are replaced by their diamagnetic analogues leaving the other magnetic sublattice untouched. By modifying the molecular field model the Nb^IV concentration dependence of the magnetic ordering temperature was reproduced and the percolation threshold was determined.