|
Si团簇的结构特性研究 |
The Study of Structural Properties for Si Clusters |
|
DOI:10.3969/j.issn.1671-5322.2003.04.004 |
中文关键词: 非正交紧束缚模型 最低能量结构 |
英文关键词: Nonorthogonal tight-binding scheme the gepmetry of the lowest energy |
基金项目: |
|
摘要点击次数: 5018 |
全文下载次数: 4355 |
中文摘要: |
采用由M.Menon等人的非正交紧束缚模型,结合遗传算法和分子动力学方法,对n=2-20的中小尺寸Si团簇的结构进行了优化,计算了团簇的束缚能Eb、平均配位数CN,裂化能Efrag,总能的二阶差分△2E,HOMO和LUMO的能隙Eg,得出了随着团簇尺寸的增加,构型发生了近球形-长椭球形-近球形的转变、n=4,7,10等团簇具有较强稳定性,团簇中原子之间共价键性结合占支配地位等主要结论.所得的主要结论与已有的从头计算和实验结果相一致. |
英文摘要: |
Using the nonorthogonal tight-binding scheme,combined with a genetic algorithm and a molecular-dynamics, obtain the geometry of the lowest energy for Si n(n =2-20)clusters, and calculate the binding energy E b per atom, average coordination numbers CN, fragmentation energy E frag, the second difference of total energy △2E, the energy gap of HOMO and LUMO E g, draw the following conclusions: as the increase of cluster size, the geometry ’near spherical-prolate-near spherical’ transition occur, Si n(n =4,7,10)clusters are the most stable, the bonding between atoms are dominated by covalency. The conclusions are in good agreement with ab inition calculation and experiments. |
查看全文
查看/发表评论 下载PDF阅读器 |
关闭 |
|
|
|