Temperature variation of the field-dependent spin reduction in the one-dimensional antiferromagnets: K2FeF5and Rb2FeF5

Abstract
Mossbauer spectra of single crystals of K2FeF5 and Rb2FeF5 show that, in accordance with spin-wave theory, the spin reduction resulting from the application of an external magnetic field, which is enhanced in one-dimensional antiferromagnets, decreases significantly when the temperature is lowered. In addition, the value of the critical field for spin flopping in K2FeF5 is reduced on lowering the temperature.