KOLCHUGINA Natalia VSB - Technical University of Ostrava

Spoluautoři BURKHANOV Gennady, DRULIS Henrik

Commercial rare-earth metals erbium and thulium were purified by vacuum distillation. The impurity composition of the metals was studied by laser mass-spectrometry analysis. Magnetism, magnetic transitions, and wide variety of magnetic structures of REMs are the distinctive feature of the metals and, in particular, can be studied and interpreted based on data on the heat capacity. The heat capacity is a fundamental characteristic of metals, which depends substantially on their purity. The use of impure metals leads to the observation of anomalies that are not related to the metal oneself and does not allow effects typical of the metal to be revealed. Two groups of impurities affecting the heat capacity of REMs is known can be specified; these are gas-forming elements (O, H, N, C) and magnetic metals (Fe, Cr, Mn, other REMs). The temperature dependences of the heat capacity of erbium and thulium and hydrogen solid solution TmH0.21 are measured in the temperature ranges of their magnetic transformations. The behavior of temperature dependence of the heat capacity of Er, namely, both the heat capacity value and existence of anomalies in the curve, demonstrate substantial dependence on the metal purity. The presence of anomalies in the temperature dependence of heat capacity of distilled Tm is related to the presence of residual hydrogen whose atoms form ordered chains; the fact is confirmed by measurements of the heat capacity of TmH0.21. This study was supported by the Branch of Chemistry and Materials Science, Russian Academy of Sciences (program no. 5).