Bridge function for liquid Na

Bridge function B(r) for liquid Na is calculated in the referense hypernetted chain approximation from the pair distribution function obtained by means of MD simulations. A comparison with the bridge function obtained in a Mori-Hoshino-Watabe scheme is made. The influence of the cut-off radius and the MD sample size on the structure factor is investigated.Елементарні діаграми B(r) для рідкого Na розраховані в базисному гіперланцюговому наближенні з парних функцій розподілу отриманих методом МД. Проведено порівняння з B(r) в наближенні Морі-Хошіно-Ватабе. Досліджено залежність статичного структурного фактора від радіуса обрізання базисної парної функції розподілу

Theoretical and computer simulation study of density fluctuations in liquid binary alloys

The dynamical properties of liquid alloys are investigated by means of memory function equations and molecular-dynamics simulation. A simple model for the second-order memory function in a binary liquid, based on Mori's memory function formalism, is proposed and applied in numerical calculations of the time correlation functions and dynamic structure factor of liquid K0.7Cs0.3 and K0.3Cs0.7 alloys. Obtained results are discussed in comparison with the results of computer simulations

Longitudinal collective modes in simple liquid binary alloys: A computer simulation study.

The dynamic collective properties of the liquid Li0.7-Mg0.3 alloy are studied by molecular-dynamics simulation. The dynamic structure factors and longitudinal current correlations at wave vectors between the hydrodynamic and kinetic regime (0.2,k, 4A 21 ) are analyzed. In order to discuss the influence of the mass difference between particles on the longitudinal modes, the same alloy, except that the mass of the heavy atoms was increased by a factor of 10, was simulated. The resulting properties are compared with those of the ordinary Li0.7-Mg0.3 alloy. It is shown that at wave vectors prior to the hydrodynamic region both fast and slow longitudinal modes of kinetic character propagate through light and heavy particles, respectively. In the hydrodynamic limit fast and slow modes merge into a single acoustic mode. It is corroborated that fast propagating modes in disparate mass liquid mixtures have a kinetic character. The number-number and concentration-concentration time correlation functions were also determined. The former shows a behavior analogous to that of the corresponding function in one-component liquids. The second reflects the existence of propagating concentration modes