COLLECTIVE DYNAMICS IN SINGLE-PARTICLE MOTION FOR PURE FLUIDS

Condensed Matter Physics

关键词: single-particle dynamics;    Lennard-Jones fluid;    velocity autocorrelation function;    diffusion;   

DOI  :  10.5488/CMP.6.1.23

来源: DOAJ

【 摘 要 】

Single-particle time correlation function F_s(k,t) of pure fluids is studied within the generalized mode approach. Analytical expression for self-intermediate scattering function, which contains oscillating terms, is obtained for three-variable basis set of single-particle dynamic variables. The meaning of oscillating contributions is discussed, and it is shown, that in low-density fluids the oscillating contributions do not appear. Our approach, developed within the five-variable scheme, is used for the analysis of MD-derived single-particle time correlation function of Lennard-Jones fluid at two densities. It is shown, that the proposed scheme allows us to reproduce perfectly the function F_s(k,t) at the whole range of wavenumbers k studied. The generalized self-diffusion coefficient as a function of k is also calculated.

【 授权许可】

Unknown