Specific heat below 3 °K of a gold–zinc and a gold–indium alloy

1969 ◽  
Vol 47 (10) ◽  
pp. 1077-1081 ◽  
Author(s):  
Douglas L. Martin
Keyword(s):  
Specific Heat ◽  
Face Centered Cubic ◽  
Electronic Specific Heat ◽  
Confidence Limits ◽  
Electric Field Gradients ◽  
Field Gradients ◽  
Atomic Silver ◽  
Face Centered ◽  
Specific Heat Coefficient ◽  
Limiting Value

Face-centered-cubic alloys of gold with 10 atomic % zinc (divalent) and 10 atomic % indium (trivalent), respectively, were measured in the range 0.4 to 3.0 °K. The coefficients of the nuclear specific-heat term were 1.80 ± 0.07 μcal °K/g atom for AuZn and 1.29 ± 0.06 μcal °K/g atom for AuIn (95% confidence limits). For a gold–10 atomic % silver (monovalent) alloy (Martin 1968) the nuclear term was 0.44 μcal °K/g atom. These results show that electric field gradients in alloys are not simply proportional to the valence difference of the components, a conclusion which may be drawn from NMR results. For the AuZn alloy the electronic specific-heat coefficient (γ) is 153.4 ± 0.7 μcal/°K2 g atom and the limiting value of the Debye temperature (θ0c) is 177.0 ± 0.5 °K. For the AuIn alloy γ is 185.9 ± 0.7 μcal/°K2 g atom and θ0c is 159.1 ± 0.3 °K.

Effect of ordering on the specific heat of Cu3Au below 3 °K

1968 ◽  
Vol 46 (8) ◽  
pp. 923-927 ◽  
Author(s):  
Douglas L. Martin
Keyword(s):  
Elastic Constant ◽  
Specific Heat ◽  
Electric Quadrupole ◽  
Quadrupole Moments ◽  
Electronic Specific Heat ◽  
Electric Field Gradients ◽  
Specific Heats ◽  
Disordered Lattice ◽  
Field Gradients ◽  
Lattice Specific Heat

Ordering reduces the nuclear, electronic, and lattice specific heats. The change in nuclear specific heat supports the hypothesis that this term in the specific heat arises from the interaction of nuclear electric quadrupole moments with electric field gradients in the disordered lattice. The small (3.5%) change in the electronic specific heat suggests little change in the Fermi surface on ordering. The change in the lattice specific heat is greater than expected from elastic constant measurements on ordered and disordered Cu3Au.

Hole density dependence of the low temperature electronic specific heat coefficient of La2-xSrxCaCu2O6 with weakly localized electrons

1993 ◽  
Vol 209 (4) ◽  
pp. 553-558 ◽  
Author(s):  
Takashi Nishikawa ◽  
Shin-ichi Shamoto ◽  
Masafumi Sera ◽  
Masatoshi Sato ◽  
Shigeki Ohsugi ◽  
...  
Keyword(s):  
Low Temperature ◽  
Specific Heat ◽  
Density Dependence ◽  
Hole Density ◽  
Electronic Specific Heat ◽  
Specific Heat Coefficient ◽  
Localized Electrons

Spin Disorder Resistivity and Electronic Specific Heat of Gd4(Co1-xCux)3 Compounds

2008 ◽  
Vol 587-588 ◽  
pp. 333-337
Author(s):  
T.M. Seixas ◽  
M.A. Salgueiro da Silva ◽  
O.F. de Lima ◽  
J. Lopez ◽  
Hans F. Braun ◽  
...  
Keyword(s):  
Specific Heat ◽  
Linear Dependence ◽  
Magnetic Moments ◽  
Spin Fluctuations ◽  
Electronic Specific Heat ◽  
Spin Disorder ◽  
Structure Changes ◽  
Thermal Disorder ◽  
Specific Heat Coefficient ◽  
Electron Band Structure

In this work, we present a study of the spin disorder resistivity ( ρm∞) and the electronic specific heat coefficient ( γ) in Gd4(Co1-xCux)3 compounds, with x = 0, 0.05, 0.10, 0.20, 0.30. The experimental results show a strongly non-linear dependence of ρm∞ on the de Gennes factor which, in similar intermetallic compounds, is usually attributed to the existence of spin fluctuations on the Co 3d bands and its amplification by the thermal disorder of the Gd magnetic moments through the Gd-Co exchange coupling. Using a novel combined analysis of ρm∞ and γ, we show, however, that only electron band structure changes are involved in the anomalous behaviour of ρm∞ and that a linear dependence of ρm∞ on the de Gennes factor is obtained when the variation of the effective mass is properly taken into account.

Specific heat below 3 °K, melting point, and melting heat of rubidium and cesium

1970 ◽  
Vol 48 (11) ◽  
pp. 1327-1339 ◽  
Author(s):  
Douglas L. Martin
Keyword(s):  
Thermal Analysis ◽  
Melting Point ◽  
Low Temperature ◽  
Specific Heat ◽  
Alkali Metals ◽  
Effective Masses ◽  
Debye Temperatures ◽  
Latent Heat Of Melting ◽  
Specific Heat Coefficient ◽  
Limiting Value

Specific heat measurements were made between 0.4 and 3.0 °K. For rubidium (nominal purity 99.9%, actual purity probably ~ 99.99%) the electronic specific heat coefficient γ is 624.6 ± 6.5 μcal/°K2 g atom and the low temperature limiting value of the Debye temperature (ΘOoc) is 56.5 ± 0.2 °K. For cesium (nominal purity 99.99%, actual purity probably ~ 99.97%) γ is 950 ± 20 μcal/°K2 g atom and ΘOoc is 40.5 ± 0.3 °K. These Debye temperatures are in fair agreement with ΘOoc1 values calculated from low temperature elastic constant measurements. Electron effective masses (calculated from γ) are 1.37 ± 0.01 for Rb and 1.80 ± 0.04 for Cs. Thermal effective masses for all the alkali metals are compared with recent theoretical results. Sample purities were checked by an independent spectrographic analysis and by making a thermal analysis in the melting region on the actual specific heat samples. These thermal analysis results led to a review of earlier work on the melting of these metals and the following revised values of melting point and latent heat of melting were obtained: Rb: 312.47 ± 0.02 °K, 524.3 ± 1.0 cal/g atom; Cs: 301.67 ± 0.13 °K, 501.0 ± 1.0 cal/g atom.

Electronic specific heat coefficient and magnetic entropy of icosahedral Mg-RE-Zn (RE=Gd, Tb and Y) quasicrystals

1995 ◽  
Vol 7 (22) ◽  
pp. 4183-4191 ◽  
Author(s):  
Y Hattori ◽  
K Fukamichi ◽  
K Suzuki ◽  
A Niikura ◽  
A P Tsai ◽  
...  
Keyword(s):  
Specific Heat ◽  
Electronic Specific Heat ◽  
Magnetic Entropy ◽  
Specific Heat Coefficient

Enhancement of the electronic specific heat coefficient in (Co1−xNix)2ScSn

1993 ◽  
Vol 73 (10) ◽  
pp. 5427-5429 ◽  
Author(s):  
C. J. Fuller ◽  
Z. W. Chen ◽  
N. Anbalagan ◽  
C. L. Lin ◽  
T. Mihalisin
Keyword(s):  
Specific Heat ◽  
Electronic Specific Heat ◽  
Specific Heat Coefficient
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