Pressure Induced Crossover between a Ferromagnetic and a Canted Antiferromagnetic State for [Bis(pentamethylcyclopentadienyl)- iron(III)][Tetracyanoethenide], [FeCp2*][TCNE]

The reversible hydrostatic pressure dependent DC magnetic behavior of the ferromagnetically ordered electron transfer salt [FeIIICp2*]*+[TCNE]*− (Cp* = pentamethylcyclopentadienide; TCNE = tetracyanoethylene) was studied up to 12.2 kbar. A significant departure from the ambient pressure ferromagnetic behavior was observed under pressure. The temperature dependent magnetization data were typical of a ferromagnet at ambient pressure but exhibited an extreme reduction with increasing applied pressure, while metamagnetic-like behavior was evident in the field dependent magnetization data at 4.2 kbar and above....