• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites >Vitreous silica bulk and surface self-diffusion analysis by molecular dynamics
【24h】

Vitreous silica bulk and surface self-diffusion analysis by molecular dynamics

机译：玻璃态二氧化硅的体积和表面自扩散的分子动力学分析

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Molecular dynamics simulation was used to investigate the kinetics of self-diffusion in the bulk and on the surface of pristine vitreous silica. Multibody potential functions were used to describe interatomic forces, Activation energies were found to be similar for Si and O self-diffusion and did not vary appreciably between self-diffusion in the bulk and an the surface. For both species in the bulk and on the surface, average activation energies ranged from 113-115 kcal/mol. Oxygen self-diffusivity was found to be only slightly higher than silicon self-diffusivity in the bulk and on the surface. Self-diffusion coefficients in the top 3-7 Angstrom of the surface were found to be higher than those of bulk simulations by less than a factor of two. Self-diffusion on the surface was observed to occur by motion of SiO3 and SiO4 polyhedra over several angstroms while bulk self-diffusion involved significant neighbor exchange over similar length scales, Surface diffusion through a vapor phase (via desorption and re-adsorption at a distant location on the surface) was not included in the surface data. (C) 1997 Elsevier Science B.V.
机译：分子动力学模拟用于研究原始玻璃体二氧化硅在本体和表面的自扩散动力学。用多体势函数来描述原子间力，发现硅和O的自扩散的活化能相似，并且在本体和表面的自扩散之间没有明显的变化。对于大部分物质和表面物质，平均活化能范围为113-115 kcal / mol。发现在本体和表面上，氧的自扩散率仅略高于硅的自扩散率。发现表面顶部3-7埃的自扩散系数比整体模拟的自扩散系数小两倍。 SiO3和SiO4多面体在几埃的运动下发生了表面自扩散，而本体自扩散涉及相似长度尺度上的大量邻域交换，通过气相的表面扩散（通过远距离的解吸和再吸附）表面上的位置）未包含在表面数据中。 （C）1997年Elsevier Science B.V.

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号