Transport properties of solid and liquid Cs

1982 ◽  
Vol 60 (12) ◽  
pp. 1759-1769 ◽  
Author(s):  
J. G. Cook

The thermal conductivity, electrical resistivity, and thermoelectric power of Cs have been measured from 40 K, through the melting point which is near 300 K, up to 600 K. The thermal resistivity of both solid and liquid Cs contains a contribution from electron–electron scattering, which agrees well with theory. The electrical resistivity shows an appreciable "premelting" effect, which is tentatively attributed to impurities.

1979 ◽  
Vol 57 (6) ◽  
pp. 871-883 ◽  
Author(s):  
J.G. Cook

The electrical resistivity, thermal conductivity, and thermoelectric power of Rb have been measured between 40 and 300 K. Two of the samples were bare, to avoid thermal contraction difficulties; the softness of these samples necessitated further, calibration, measurements on a third sample in glass, just below the freezing point. The electrical resistivity values agree well with published values of Dugdale and Phillips. The Lorenz function, not previously examined in detail above 25 K, shows strong evidence of electron–electron scattering, of a strength intermediate to that calculated by Kukkonen for Thomas–Fermi screening, and for Geldart–Taylor screening. Such scattering appears to have affected the thermoelectric power as well.


1979 ◽  
Vol 57 (8) ◽  
pp. 1216-1223 ◽  
Author(s):  
J. G. Cook

The electrical resistivity ρ, thermal conductivity κ, and thermoelectric power S have been measured for two bare K specimens between 80 and 330 K. The data fully support the main conclusions of an earlier, preliminary study by Cook and Laubitz. The Lorenz function L = κρ/T does not approach the Sommerfeld value L0 with increasing temperature. Both the magnitude and temperature dependence of L–L0 indicate the presence of an added term Wee in the thermal resistivity, due to electron–electron scattering. Such scattering also affects S. It is shown that the data for K, together with published values of B = Wee/T for Na, Rb, and the noble metals, form a consistent picture of electron–electron scattering in the monovalent metals above the Debye temperature.


1975 ◽  
Vol 53 (5) ◽  
pp. 486-497 ◽  
Author(s):  
J. G. Cook ◽  
M. J. Laubitz ◽  
M. P. Van der Meer

Data are presented for the thermal and electrical resistivity and thermoelectric power of two samples of Ca (having residual resistance ratios of 10 and 70) between 30 and 300 K. Large deviations from both Matthiessen's rule and the Wiedemann–Franz relationship are observed. The former are tentatively attributed to the presence of two distinct groups of carriers in Ca, and analyzed using the two band model. The latter deviations are interpreted as the effects of band structure. The thermoelectric power of Ca is large. In many respects the transport properties of Ca appear to be similar to those of the transition metals.


1966 ◽  
Vol 44 (10) ◽  
pp. 2293-2302 ◽  
Author(s):  
H. L. Malm ◽  
S. B. Woods

Low-temperature measurements of electrical resistivity, thermal conductivity, and thermoelectric power on silver alloys containing 0.005, 0.067, 0.11, and 0.31 at.% of manganese are reported. The same specimens were used for the measurement of all properties over the temperature range from 2 to 25 °K. The well-known minimum and maximum are observed in the electrical resistivity of the three more concentrated alloys and the minimum is visible in the most dilute alloy near the lowest temperatures of measurement. Associated effects are observed in the other properties and their possible relationship to theoretical electron scattering mechanisms, particularly that of Kondo, is discussed.


1981 ◽  
Vol 59 (1) ◽  
pp. 25-34 ◽  
Author(s):  
J. G. Cook

We report the results and interpretation of precision measurements of the thermal conductivity, electrical resistivity, and thermopower of potassium made from just below the melting temperature, 335.5 K, to 700 K. It is found that the Lorenz function is approximately 10% below the Sommerfeld value in the solid state, confirming previously reported data, that it increases approximately 4% upon melting, and that it then decreases slightly upon further heating to 700 K. All these features may be explained very well by the combined effect of electron–electron scattering and of scattering of electrons by ionic density fluctuations.


1982 ◽  
Vol 60 (9) ◽  
pp. 1311-1316 ◽  
Author(s):  
J. G. Cook ◽  
M. P. van der Meer ◽  
D. J. Brown

Equipment to perform low-level thermocouple thermometry using a computer, a digital voltmeter, and very low thermal offset switching has been used to measure the thermal conductivity, electrical resistivity, and thermoelectric power of Rb from its melting point, near 313 K, to 650 K. The data obtained, which are accurate to the percent level, may be explained by combining the effect of the elastic scattering of electrons by ionic density fluctuations, and the effect of electron–electron scattering.


2003 ◽  
Vol 793 ◽  
Author(s):  
Y. Amagai ◽  
A. Yamamoto ◽  
C. H. Lee ◽  
H. Takazawa ◽  
T. Noguchi ◽  
...  

ABSTRACTWe report transport properties of polycrystalline TMGa3(TM = Fe and Ru) compounds in the temperature range 313K<T<973K. These compounds exhibit semiconductorlike behavior with relatively high Seebeck coefficient, electrical resistivity, and Hall carrier concentrations at room temperature in the range of 1017- 1018cm−3. Seebeck coefficient measurements reveal that FeGa3isn-type material, while the Seebeck coefficient of RuGa3changes signs rapidly from large positive values to large negative values around 450K. The thermal conductivity of these compounds is estimated to be 3.5Wm−1K−1at room temperature and decreased to 2.5Wm−1K−1for FeGa3and 2.0Wm−1K−1for RuGa3at high temperature. The resulting thermoelectric figure of merit,ZT, at 945K for RuGa3reaches 0.18.


1957 ◽  
Vol 35 (8) ◽  
pp. 892-900 ◽  
Author(s):  
G. K. White ◽  
S. B. Woods

Measurements of the thermal conductivity from 2° to 90 ° K. and electrical conductivity from 2° to 300 ° K. are reported for vanadium, niobium, and hafnium. Although the vanadium and hafnium are not as pure as we might wish, measurements on these metals and on niobium allow a tabulation of the "ideal" electrical resistivity clue to thermal scattering for these elements from 300 ° K. down to about 20 ° K. Ice-point values of the "ideal" electrical resistivity are 18.3 μΩ-cm. for vanadium, 13.5 μΩ-cm. for niobium, and 29.4 μΩ-cm. for hafnium. Values for the "ideal" thermal resistivity of vanadium and niobium are deduced from the experimental results although for vanadium and more particularly for hafnium, higher purity specimens are required before a very reliable study of "ideal" thermal resistivity can be made. For the highly ductile pure niobium, the superconducting transition temperature, as determined from electrical resistance, appears to be close to 9.2 ° K.


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