Short-time dynamics of a tracer in an ideal gas

Analysis of Non-Gaussian Diffusion of Hydrogen and Oxygen in Cement Paste Using a Two-State Fluctuating Diffusivity Model

“…4. At the short time scale, the magnitudes of the non-Gaussian pa-rameter are large, compared with some media like simple argon liquid, 41) binary gas mixtures, [42][43][44] or even with super-cooled liquids. 45) Physically, the magnitude of the non-Gaussianity means the degree of heterogeneity of the particle diffusivity.…”

Effect of film thickness and temperature on condensation and momentum accommodation at the liquid–vapor methane interphase in contact with a quartz substrate

“…Quantitatively, we can reason that the velocity correlation coefficient of a particle after number N col of independent collisions, γ N col , is equal to γ N col 1 , where γ 1 is the velocity correlation coefficient after one collision. This coefficient is equal to 3/7 for hard sphere intermolecular potential [44]. As γ 1 < 1, the correlation decreases exponentially to 0 with the number of collisions N col increasing.…”