Temperature dependence of transport properties in liquid metals.

摘要

Using the Ziman formula, which results from solving the linearized Boltzmann equation, the electrical and thermal resistivities of selected metals in the liquid state are calculated over a range of temperatures, at and above the melting point. In previous studies of liquid metals, the electrical resistivity was calculated for only a very few cases and only at the melting point. In most cases the calculated structure factor S(q), if used, was obtained from simple models like the hard sphere or empty-core pair potential model. By doing the calculations over a range of temperatures, beyond the melting point and using a better S(q), we gain considerable insight into the transport properties of liquid metals. By calculating the thermal resistivity over the same range of temperatures we explain the deviation of the ratio of electrical and thermal resistivities from the Wiedemann-Franz law, which holds well for lower temperatures.; The form factor is calculated for each liquid metal based on the model potential suggested by Taylor et al., including screening effects, by using the screening function of Geldart and Taylor. The liquid structure factors are calculated, in some cases, from the radial distribution function obtained from Monte Carlo simulations based on the same model potential mentioned above and used in the form factor construction. Both the calculated structure factors and the experimental structure factors obtained from x-ray scattering are used in the Ziman formula to obtain the thermal and electrical resistivities. The results are compared to experimental values and to other theoretical calculations done at the melting point for each of the selected metals using different model potentials and form factors or other theoretical methods.