Vollmayr-Lee, Katharina and Roman, Jeff A. and Horbach, Jürgen
(2010)
*Aging to equilibrium dynamics of SiO2.*
Physical Review E, 81 (6), 061203.
DOI: 10.1103/PhysRevE.81.061203.
ISSN 1539-3755.

Full text not available from this repository.

Official URL: http://pre.aps.org/abstract/PRE/v81/i6/e061203

## Abstract

Molecular dynamics computer simulations are used to study the aging dynamics of SiO2 (modeled by the BKS model). Starting from fully equilibrated configurations at high temperatures T-i is an element of {5000 K, 3760 K}, the system is quenched to lower temperatures T-f is an element of {2500 K, 2750 K, 3000 K, 3250 K} and observed after a waiting time t(w). Since the simulation runs are long enough to reach equilibrium at Tf, we are able to study the transition from out-of-equilibrium to equilibrium dynamics. We present results for the partial structure factors, for the generalized incoherent intermediate scattering function C-q(t(w), t(w) + t), and for the mean-square displacement Delta r(2)(t(w), t(w) + t). We conclude that there are three different t(w) regions: (I) At very short waiting times, C-q(t(w), t(w) + t) decays very fast without forming a plateau. Similarly Delta r(2)(t(w), t(w) + t) increases without forming a plateau. (II) With increasing tw a plateau develops in C-q(t(w), t(w) + t) and Delta r(2)(t(w), t(w) + t). For intermediate waiting times the plateau height is independent of t(w) and T-i. Time superposition applies, i.e., C-q=C-q(t/t(r)(Cq)) where t(r)(Cq)=t(r)(Cq)(t(w)) is a waiting time-dependent decay time. Furthermore C-q=C(q, t(w), t(w) + t) scales as C-q=C(q, z(t(w), t) where z is a function of t(w) and t only, i.e., independent of q. (III) At large t(w) the system reaches equilibrium, i.e., C-q(t(w), t(w) + t) and Delta r(2)(t(w), t(w) + t) are independent of t(w) and T-i. For C-q(t(w), t(w) + t) we find that the time superposition of intermediate waiting times (II) includes the equilibrium curve (III).

Document Type: | Article | ||||||||
---|---|---|---|---|---|---|---|---|---|

Title: | Aging to equilibrium dynamics of SiO2 | ||||||||

Authors: |
| ||||||||

Date: | 25 June 2010 | ||||||||

Journal or Publication Title: | Physical Review E | ||||||||

Refereed publication: | Yes | ||||||||

In Open Access: | No | ||||||||

In SCOPUS: | Yes | ||||||||

In ISI Web of Science: | No | ||||||||

Volume: | 81 | ||||||||

DOI: | 10.1103/PhysRevE.81.061203 | ||||||||

Page Range: | 061203 | ||||||||

ISSN: | 1539-3755 | ||||||||

Status: | Published | ||||||||

Keywords: | GLASS TRANSITION; COMPUTER SIMULATION; AGING | ||||||||

HGF - Research field: | Aeronautics, Space and Transport (old) | ||||||||

HGF - Program: | Space (old) | ||||||||

HGF - Program Themes: | W FR - Forschung unter Weltraumbedingungen (old) | ||||||||

DLR - Research area: | Space | ||||||||

DLR - Program: | W FR - Forschung unter Weltraumbedingungen | ||||||||

DLR - Research theme (Project): | W - Vorhaben Materialwissenschaftliche Forschung (old) | ||||||||

Location: | Köln-Porz | ||||||||

Institutes and Institutions: | Institute of Materials Physics in Space | ||||||||

Deposited By: | Dr.rer.nat. Jürgen Horbach | ||||||||

Deposited On: | 05 Nov 2010 09:59 | ||||||||

Last Modified: | 16 Feb 2016 05:04 |

Repository Staff Only: item control page