Crossover to Potential Energy Landscape Dominated Dynamics in a Model Glass-forming Liquid

Дата и время публикации : 1999-01-25T19:47:17Z

Авторы публикации и институты :
Thomas B. Schroeder
Srikanth Sastry
Jeppe C. Dyre
Sharon C. Glotzer

Ссылка на журнал-издание: J. Chem. Phys. 112, 9834 (2000)
Коментарии к cтатье: Expanded from 4 to 7 pages
Первичная категория: cond-mat.soft

Все категории : cond-mat.soft, cond-mat.dis-nn, cond-mat.stat-mech

Краткий обзор статьи: An equilibrated model glass-forming liquid is studied by mapping successive configurations produced by molecular dynamics simulation onto a time series of inherent structures (local minima in the potential energy). Using this “inherent dynamics” approach we find direct numerical evidence for the long held view that below a crossover temperature, $T_x$, the liquid’s dynamics can be separated into (i) vibrations around inherent structures and (ii) transitions between inherent structures (M. Goldstein, J. Chem. Phys. {bf 51}, 3728 (1969)), i.e., the dynamics become “dominated” by the potential energy landscape. In agreement with previous proposals, we find that $T_x$ is within the vicinity of the mode-coupling critical temperature $T_c$. We further find that at the lowest temperature simulated (close to $T_x$), transitions between inherent structures involve cooperative, string like rearrangements of groups of particles moving distances substantially smaller than the average interparticle distance.

Category: Physics