Magnetic properties of the RCo3Sn (R=Gd to Tm) compounds

The RCo3Sn compounds where R=Gd to Tm, as well as the new SmCo3Sn, have bee n synthesised and their magnetic properties investigated from 4 to 300 K an d under 7-9 T. These alloys order ferromagnetically, the Curie temperatures ranging from 10 K for R=Tm to 130 K for R=Gd. Their magnitude together wit h their linear variation versus the 'de Gennes' factor tend to show that Co is not magnetic in this series. Besides, a smooth superimposed metamagneti c type behaviour occurs in GdCo3Sn below 22 K around 1.2 T. (C) 2000 Elsevi er Science B.V. All rights reserved.