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

被引:63
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
收藏
页码:2681 / 2687
页数:7
相关论文
共 30 条