Seiichi Naito

Isothermal compressibility and sound velocity of liquid rare earth metals

Abstract The simple one-component plasma (OCP) model has been applied to the isothermal compressibilities of liquid rare earth metals. The calculated results are in fair agreement with those estimated from the long-wavelength limit of liquid structure factors and the well-known relation between the isothermal compressibility and the surface tension. The velocity of sound has been calculated by the Percus-Yevick (PY) phonon model using recently measured low-angle structure data. The OCP model appears to provide a fair description of the thermodynamic properties of liquid rare earth metals.

Entropies and specific heats of liquid transition metals: one-component plasma model

A simple one-component plasma model is capable of describing the entropies and specific heats (Cv and Cp) of liquid 3d transition metals near the melting points. The agreement between theoretical and experimental values is remarkably good for the entropies.

Specific heats of liquid transition metals calculated from the temperature derivative of the one-component plasma structure factor

Abstract Successful specific heat calculations of liquid 3d transition metals near the melting points are presented. The calculations are based on the collective coordinate method using the temperature derivative of the one-component plasma structure factor. The overall agreement between theory and experiment is very reasonable including the ratio of specific heats.

A molecular dynamics study of expanded liquid rubidium

Molecular dynamics calculations for expanded liquid rubidium are reported. Effective interatomic pair potentials estimated from low-angle structure factors have been used in this study. Results for the radial distribution function, the structure factor, the mean-square displacement, the velocity autocorrelation function and the self-diffusion constant are given and discussed. Finally, the effective pair potential for 1900°K is discussed in comparison with those derived from nearly-free-electron linear response theory

Effective valencies of liquid 3d transition metals estimated from the Gibbs-Bogoliubov variational method using the one-component plasma reference system

We present the effective valencies of liquid 3d transition metals estimated from the Gibbs-Bogoliubov variational method using the classical one-component plasma reference system. The effective pair interactions are calculated within the framework of the simple-metal theory. We employ the Ashcroft empty-core form for the s-electron pseudopotential. The value of the core radius is uniquely determined by the density of the system of interest. The effective valencies determined from the variational method are compatible with those obtained from other theoretical works. The calculated values of the long-wavelength limit of the structure factor are in excellent agreement with the available experimental values.

Thermal pressure coefficients of liquid alkali metals: One-component plasma model

Abstract The pressure equation appropriate to liquid metals is applied to the calculations of the thermal pressure coefficients of alkali metals using the pseudopotential formalism for the electron-ion interaction. The density dependence of both pair potential and structure factor is taken into account in this analysis. Agreement between theory and experiment is found satisfactory.

Thermal pressure coefficients of liquid 3d transition metals using the one-component plasma reference system

A modified form of the pressure equation appropriate to liquid metals is applied to the calculations of the thermal pressure coefficients of liquid transition metals. The density dependence of both the pair potential and the one-component plasma structure factor is taken into account in this analysis. A comparison is made with the hard sphere reference system to understand the role of softness in the panpotential on the thermal pressure coefficients of liquid transition metals.

The structure and effective pair potential of liquid manganese near the melting point

A simple-metal theory can describe, in some favorable cases, the structures of liquid 3d transition metals when the pseudopotential parameters are chosen appropriately. This is shown, using the Percus-Yevick integral equation, for liquid manganese which has a half-filled d band and is claimed to be difficult to handle theoretically. The Ashcroft empty-core form for the s-electron pseudopotential is employed. The value of core radius is determined from the density of liquid manganese at 1533 K and the effective valence, Zs, is determined by the value of the plasma parameter with which the liquid structures and thermodynamic properties are well described by the one-component plasma (OCP) model. The validity of the value of Zs is supported by the Gibbs-Bogoliubov method using the OCP reference system.