抄録
Pressure and compressibility of simple metals such as alkali metals, Zn, Al and Pb are calculated in the liquid state near the triple point, using the pseudopotential formalism for electron-ion interaction. Effective ion-ion interaction is defined naturally by calculating the total energy of metals to the second order of the electron-ion pseudopotential and its contributions to pressure and bulk modulus are calculated separately by the use of the so-called pressure equation of state modified properly to include the effects of the density-dependence (due to the electronic screening effect) of the effective ion-ion potential. It is found that these contributions are much larger (of more repulsive nature) than those estimated by using the Percus-Yevick solution for the hard-sphere model. The effects of the density dependence of the ion-ion interaction are found quite important for the pressure in alkali metals. Comparison of the calculated values of compressibility with experiments is made and the agreement is found satisfactory.
