SYNTHESES AND CHARACTERIZATIONS OF RARE EARTH COMPOUNDS RE(HCO2)3(HNO2)(H2CO2)(RE = Y, TB, DY, HO, ER, YB, TM)

Abstract

A series of novel inclusion compounds with compositions of RE(HCO2)3(HNO2)(H2CO2) (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) C2221 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 H2CO2 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 RE3+ ions. The yttrium compound shows very weak temperature independent paramagnetism.