Synthesis and Characterizations of Rare Earth Compounds RE(HCO 2) 3(HNO 2)(H 2CO 2)(RE=Y, Tb, Dy, Ho, Er, Yb, Tm)

A series of novel inclusion compounds with compositions of RE(HCO 2) 3(HNO 2)(H 2CO 2) (RE=Y, Tb, Dy, Ho, Er, Yb, Tm) were synthesized and structures were characterized by X ray methods. The orthorhombic structure was shown to be a new type with a non centrosymmetric space group (20) C 222 1 by single crystal structure determinations. It is characterized by networks of rare earth centered square anti prisms formed by eight oxygen atoms through bridging carbon and nitrogen atoms. The guest formic acid molecules H 2CO 2 are distributed inside the open tunnels along the crystallographic a axis. The magnetic susceptibility measurements show the heavy rare earth compounds follow the Curie Weiss law and the calculated numbers of Bohr magnetons are consistent with the RE 3 ions. The yttrium compound shows very weak temperature independent paramagnetism.