Physicochemical study of the yttrium subgroup rare earths monochloroacetates

Monochloroacetates of the series of yttrium subgroup rare earths are prepared: Ho, Er, Tm, Yb, Lu. Thermal stability of the prepared salts is studied. Recomposition temperatures of the investigated salts are close to one another. Thermolysis of the salts proceeds in three stages. Chlorine introduction into acetate-ion promotes considerable decrease of the monochloroacetates decomposition tempertature in comparison with acetates. Rare earths oxychlorides are the stable interstitial products of decomposition. However they decompose with formation of Ln2O3 sesquioxides of cubic form of Mn2O3 type in the temperature range of 700-1000 deg C. The thermolysis scheme of the yttrium subgroup rare earths monochloroacetates is proposed