کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
977891 933220 2008 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A statistical-mechanical theory of self-diffusion in glass-forming liquids
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات فیزیک ریاضی
پیش نمایش صفحه اول مقاله
A statistical-mechanical theory of self-diffusion in glass-forming liquids
چکیده انگلیسی

A statistical-mechanical theory of self-diffusion in glass-forming liquids is presented. A non-Markov linear Langevin equation is derived from a Newton equation by employing the Tokuyama–Mori projection operator method. The memory function is explicitly written in terms of the force-force correlation functions. The equations for the mean-square displacement, the mean-fourth displacement, and the non-Gaussian parameter are then formally derived. The present theory is applied to the glass transitions in the glass-forming liquids to discuss the crossover phenomena in the dynamics of a single particle from a short-time ballistic motion to a long-time self-diffusion process via a ββ (caging) stage. The effects of the renormalized friction coefficient on self-diffusion are thus explored with the aid of analyses of the simulation results by the mean-field theory proposed recently by the present author. It is thus shown that the relaxation time of the renormalized memory function is given by the ββ-relaxation time. It is also shown that for times longer than the ββ-relaxation time the dynamics of a single particle is identical to that discussed in the suspensions.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica A: Statistical Mechanics and its Applications - Volume 387, Issue 21, 1 September 2008, Pages 5003–5011
نویسندگان
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