Electrical resistivity lutetium

Abstract. One more method of study of the short-range order kinetics of H-atoms over tetrahedral interstices in lutetium (Lu) is proposed. It can be realized by the using of available data of measurements of heat capacity for h.c.p.-Lu-H interstitial solid solutions during the isothermal annealing. Comparison of estimated-parameters data from heat capacity and residual electrical-resistivity measurements is performed. It is shown that kinetics of heat capacity and residual resistivity at low temperatures is caused by the unique nature (short-range order relaxation) and can be described by two relaxation times at least. 

This work is concerned with a further analysis of the short-range order kinetics of hydrogen (H) atoms at tetrahedral interstices in h.c.p. lattice of lutetium (Lu). We compare the results obtained from independent investigation methods for different characteristics—residual electrical resistance [4,5] and heat capacity [6], and reveal the same nature of their conditionality. 

Smidt (1962) investigated electrical resistivity of several rare earth alloys including the Gd-Lu system. His investigation established the existence of complete solid solubiUty for the hep phase (aGd and Lu) of this system. But since there is no high temperature bcc phase for lutetium, the jSGd phase must terminate somewhere in the Gd-Lu system we estimate it to be —40 at% Lu (see section 3.3). 

Smidt (1962) and Smidt and Daane (1963) investigated electrical resistivity of several rare earth alloy systems and reported the existence of complete solubility in the terbium-lutetium system as confirmed by X-ray diffraction and resistivity methods. This result was not unexpected since these metals satisfy the Hume-Rothery requirements for formation of extensive solid solutions similar valence, electronegativities and crystal structures, and have a difierence in metalUc radii of less than 3%. 

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