The i.r. spectra of several rare-earth formates

The i.r. spectra of some rare-earth formates are recorded in the range 4000-40 cm-1. The following compounds were studied: Ce(HCO2)3, Pr(HCO2)3, Nd(HCO2)3, Sm(HCO2)3, Eu(HCO2)3 and Gd(HCO2)3. Some compounds were also studied upon deuteration and at lowered temperature. Nearly all bands could be assigned and the expected factor group splitting was observed. A shift to higher frequencies was observed with increasing atomic number.