FERRIMAGNETISM IN FECOF5.2H2O

The magnetic susceptibility of FeCoF5·H2O was measured over the temperature range from 3 to 296°K. A ferrimagnetic phase transition was observed at 27.0±0.25°K. At temperatures between 80 and 296°K FeCoF5 · 2H2O was paramagnetic and could be described by the Curie-Weiss law χ = C/(T + θ) with θ = 56°K and an effective magnetic moment per formula unit of 6.8±0.1 μB. In the ordered region the magnetization did not saturate at fields up to 11 kOe. At applied fields above 500 Oe the magnetization departed from the usual Brillouin behavior suggesting the occurrence of a second ordered phase at temperatures below 10°K. © 1979 American Institute of Physics.