权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Structural study of molocular adsorption system by use of low temperature STM/AFM and Synchrotron radiation

利用低温STM/AFM和同步辐射进行分子吸附系统的结构研究

基本信息

批准号：
09650720
负责人：
YAGI Shinya
金额：
$ 2.05万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

The adsorption structure of CH_3CN and C_5H_5N molecules on Si (111) 7*7 surface have been studied by scanning tunneling microscopy (STM). The molecular adsorption sites are crossing the domain boundary of the 7*7 unit. The adsorption structure is caused by dipole-dipole interaction between adsorbed molecule and the Si (111) 7*7 surface. In the STM images at negative sample bias, aniline molecules were observed as bright ring-like feature. It was found that aniline molecules adsorbs on the center adatom site with its amino group oriented to the rest atom site. The difference in the reactivity of the various sites on Si (111) 7*7 surface to aniline was observed. The. center adatom site is more reactive than the corner adatom one. With increasing aniline molecular the STM coverage, the aniline chain which consists of 2-8 aniline molecules was observed. From images obtained at various sample bias, this aniline chain has different electronic structure from single aniline molecule adsorbed on the Si (111) 7*7 surface. This suggests that aniline molecules polymerize on the Si (111) 7*7 surface.In the research which used the synchrotron radiation light, the preparation for the beamline and the surface structure analysis system were designed. The synchroton radiation light which can be used is an energy area from 1800 to 4000eV, and the X-ray absorption fine structure (XAFS) measurement of K absorption edge from silicon to the potassium clement is possible.

本文用扫描隧道显微镜（STM）研究了CH_3CN和C_5H_5N分子在Si（111）7*7表面的吸附结构。分子吸附位点穿过7*7单元的域边界。吸附结构是由吸附分子与Si（111）7*7表面的偶极-偶极相互作用引起的。在负样品偏压下的STM图像中，苯胺分子被观察到明亮的环状特征。结果表明，苯胺分子吸附在中心吸附原子位上，其氨基朝向其余原子位。观察到Si（111）7*7表面上的不同位置对苯胺的反应性的差异。的.中心吸附原子位置比角吸附原子位置更活泼。随着苯胺分子量的增加，STM的覆盖度增加，苯胺链由2-8个苯胺分子组成。从不同样品偏压下得到的图像来看，该苯胺链具有与吸附在Si（111）7*7表面上的单个苯胺分子不同的电子结构。在利用同步辐射光源的研究中，设计了光束线的制备和表面结构分析系统。可以使用的同步辐射光的能量范围为1800 - 4000 eV，并且可以进行从硅到钾的K吸收边的X射线吸收精细结构（XAFS）测量。