摘要:

In this note we show that the relaxation mechanism for self diffusion in solid transition metals leads quite naturally to a minimum in self diffusion coefficient at the half filled 3d, 4d and 5d-bands. We also loosely apply this concept to liquid transition metals where the relaxation is modelled as a local region of vaporization in the liquid (i.e. S(q) for large q is locally fluctuating wildly) and show that, if one can assume an Arrhenius D = D0e−/kTto a liquid metal, then the relaxation mechanism also predicts a minimum in self diffusion coefficint at the half filled 3d, 4d and 5d-bands for liquid transition metals. This prediction is shown to agree with the limited, scattered data for self diffusion in liquid transition metals

ISSN:0031-9104    

DOI:10.1080/00319107608084102

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

We utilize the concept of electron-phonon dominated optical conductivity and the Drude theory of optical properties of metals, as applied by Ujihara1, and the theory of melting in simple metals of Omini,2based on the Percus-Yevick3collective coordinate (liquid phonon) theory of simple liquids, to calculate the optical reflectivity in a variety of liquid metals. We compare the reflectivity of the metals treated by Ujihara, and extended by Siegel4(Ag, Au, Al, Cu, Fe, Ni, Co) at their melting temperatures in the solid and liquid phases to determine if the change in phonon spectrum and electronphonon collision frequency in the solid to the Percus-Yevick “liquid phonon spectrum” and electron-liquid phonon collision frequency in the liquid affects the optical properties. Later we extend the calculations of reflectivity in the liquid metals beyond their melting temperatures. This is a valid criterion of whether the Percus-Yevick liquid phonon approach to electron-disorder scattering in liquid metals is applicable in evaluating the high frequency, optical properties of liquid metals, since we can readily determine of the calculated melting entropy of Ujihara corresponds to an expected change in the optical conductivity, dielectric constant and reflectivity

ISSN:0031-9104    

DOI:10.1080/00319107608084103

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

In this note we point out that the maxima in surface tension and visosity that liquid transition metals exhibit versus d-delectron to atom ratio (d-bandfilling) via a sharp peak at the half filled 3d, 4d or 5d-band is related to the pead in cohesive energy and melting temperature at the half filled d-band exhibited for solid 29 transition metals of all three transition series. We argue that this provides eivdence for the ocncept that d-electron bonding carries over from the solid to liquid state as the transiton metal melts

ISSN:0031-9104    

DOI:10.1080/00319107608084104

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

A theory of the three partial structure factors of an A-B alloy containing AμBvcomplexes is set up as composites of the structure factors for the three component system. Applying the theory to liquid Ga with Ga2complexes, the shoulder observed on the liquid structure factor at 50°C is interpreted as arising from bond-centre (Ga2)-Ga correlations

ISSN:0031-9104    

DOI:10.1080/00319107608084105

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The thermodynamics of binary alloy phase diagrams of ascending and minimum types is shown to lead to a rather direct relation between the ratio of the slopes of the liquidus and the solidus curves, at a given temperature T, and the ratio <(δc)21(δc)2sof the concentration fluctuations in the liquid and the solid solutions. The latent heats of the two pure components also enter in a direct manner, as could have been anticipated from the results of ideal solution theory

ISSN:0031-9104    

DOI:10.1080/00319107608084106

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The significant structure theory of hydrocarbons such as methane, ethane, propane, i-butane, and n-butane has been applied to the physical adsorption on the homogeneous surface, occuring in the submonolayer region. The partition function for the two dimensional fluid adsorbed on the surface has been derived by considering the hindered rotation in the adsorbed phase.

ISSN:0031-9104    

DOI:10.1080/00319107608084107

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

From neutron elastic scattering measurements using the technique of isotopic enrichment, the parital structure factors of silver chloride are obtained.

ISSN:0031-9104    

DOI:10.1080/00319107608084108

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor