ORIGINS OF THE 2-STEP RELAXATION AND THE BOSON PEAK IN AN ALKALI SILICATE GLASS STUDIED BY MOLECULAR-DYNAMICS SIMULATION

被引：64

作者：

HABASAKI, J ^{[1
]}

OKADA, I ^{[1
]}

HIWATARI, Y ^{[1
]}

机构：

[1] KANAZAWA UNIV,KANAZAWA,ISHIKAWA 92011,JAPAN

来源：

PHYSICAL REVIEW E | 1995年 / 52卷 / 03期

关键词：

D O I：

10.1103/PhysRevE.52.2681

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

A molecular-dynamics simulation of lithium metasilicate (Li2SiO3) has been performed. A clear two-step relaxation was observed at 700 K in a density correlation function (self-part) for Li ions following an exponential decay by vibrational motion. Oscillation is found in the second (beta relaxation) region of the function, which is attributed to the so-called ''boson peak.'' The oscillation is clearer for O and Si than for Li. The slowest relaxation (alpha relaxation) can be well fitted to a stretched exponential form, and an origin of this type of decay Is confirmed to be a waiting time distribution of jump motions. Both the beta relaxation and the boson peak are found to be due to correlated motion.

引用

页码：2681 / 2687

页数：7

共 30 条

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