| 报告题目： |
Mixed alkali effect in bulk silicate glass |
| 报告人： |
Prof. Wai-Yim Ching |
| 报告人单位： |
University of Missouri-Kansas City |
| 报告时间： |
6月27日 星期二上午10:30 |
| 报告地点： |
科技楼东408 |
| 报告人简介： |
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Wai-Yim Ching是美国堪萨斯密苏里大学物理与天文系杰出的物理学教授，从事凝聚态理论和计算材料科学的研究，发表400余篇文章，H指数65。他是世界陶瓷协会院士，美国陶瓷协会、美国物理学会和英国皇家化学学会的会士。美国陶瓷学会杂志副主编。
Wai-Yim Ching is a Distinguished Curators’ Professor of Physics at the University of Missouri-Kansas City, USA. He leads the Electronic Structure Group (ESG) in the Department of Physics and Astronomy. His research focuses on condensed matter theory and computational materials science using first-principles methods. With more than 35 years of experience, he is an author or co-author of over 410 journal articles with Google Scholar H-factor 65. He is an Academician of World Ceramic Academy, a Fellow of the American Ceramic Society, Fellow of the American Physical Society, and the Fellow of the Royal Society of Chemistry. He is an Associate Editor of the Journal of the American Ceramic Society and is on the Editorial Board of Nature Scientific Reports. |
| 报告摘要： |
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A density functional theory (DFT) based ab initio molecular dynamics (AIMD) has been applied to simulate models of single and mixed alkali silicate glasses with two different molar concentrations of alkali oxides. The structural environments and spatial distributions of alkali ions in the 10 simulated models with 20% and 30% of Li, Na, K and equal proportions of Li-Na and Na-K are studied in detail for subtle variations among the models. Quantum mechanical calculations of electronic structures, interatomic bonding, mechanical and optical properties are carried out for each of the models and the results are compared with available experimental observation and other simulations. The calculated results are in good agreement with the experimental data. A quantum mechanical metric, the total bond order density (TBOD) is used to characterize internal cohesion in these glass models. A mixed alkali effect (MAE) is noted only in the calculated mechanical properties but not obvious in other bulk properties. It is shown that the Li doping deviates from expected trend due to the much stronger Li-O bonding than those for Na and K doping. |
