Residual electrical resistivity

Dilute gold alloys with Cu, Ag, Ni, Pd, and Pt as absorbers Correlation of isomer shift with residual electrical resistivity, wave function at Fermi level, s--band population of gold... 

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. 

Keywords short-range order, relaxation time, heat capacity, residual electrical resistivity... 

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. 

Changing a heat capacity, Cp, in above-mentioned equations into the residual electrical resistivity, p, they can be reduced to the corresponding kinetics models as applied to describe the results of residual resistivity measurements [5] for LuHo.igo and LuHo.254- Experimental [5] and theoretical [7], [8] results of investigation of the short-range order relaxation in LuHq.iso and LuHo.254 poly crystals were obtained from data about measurements of residual-resistivity-time dependence and are presented in Fig. 1 (b). These results we described within the framework of the first- and second-order kinetics models as well (see Fig. 1(b)). Migration energies for LuHq.iso and LuHo.254 solid solutions were evaluated and are listed in Table 1. 

Several workers have attempted to rationalise the chemical isomer shifts observed at Au impurity nuclei in various metals with limited success [102, 103]. The most comprehensive set of data comes from Barrett et al. [104], who doped Pt into 20 metals. The shift correlates very approximately with the electronegativity of the host, and a crude interpretation is that electrons are transferred in v ing degrees to the 6j-shell of the gold. An estimate of bR/R — 1-9(6) X 10 was obtained. Additional evidence in favour of an increased 6. -population has come from a comparison of the shift and residual electrical resistivity of Au alloys with Cu, Ag, Pd, and Pt [105]. The pressure dependence up to 70-6 kbar of the chemical isomer shift in a gold foil at 4-2 K has been obtained and with detailed analysis leads to a value for bR/R of +l-5 X 10- [106]. 

Smirnov and Tamarchenko 1977). Here A = p /L, po is the residual electrical resistance and Wi the ideal thermoresistance due to electron scattering by lattice vibrations. 

Table 3.1-203 Residual electrical resistivity ratio (RRR) of pure noble metals [1.217, p. 156]...

Using the Wiedemaiui-Franz law, the coefficient a can be determined from the residual electrical resistivity po. Least-squares fits to the experimental data up to 75 K are given by the solid lines in the inset of fig. 108. Interestingly the fit procedure shows that the term is much smaller compared to IFe.sf in these RC02 series. The linear... 

Fig. 1. A schematic representation of the temperature variation of the electrical resistivity, p, for a ferromagnetic compound. The arrow indicates the ferromagnetic transition. Included in the picture is the calculated temperature dependence of p , (Pspd Pmt T > Pph obtained from the Bloch-Griinedsen relation and the residual electrical resistivity pp.

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