Formation of two-dimensional mixed crystals on graphite observed by scanning tunneling microscopy

被引:24
作者
Stevens, F
Dyer, DJ
Walba, DM
机构
[1] UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309
[2] UNIV COLORADO,CTR OPTOELECTR COMP SYST,BOULDER,CO 80309
关键词
D O I
10.1021/la950960c
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Scanning tunneling microscopy (STM) is a powerful tool for observing organic molecules in real space. In this study, five similar ferroelectric liquid crystal (FLC) materials (four unsaturated isomers and the saturated parent) adsorbed on graphite were examined by scanning tunneling microscopy as neat compounds and as mixtures. The unit cells of adsorbed monolayers formed by the mixtures showed distinct differences from the unit cells of the pure compounds, suggesting that mixed monolayers were formed. The saturated compound formed two structures having different unit cells, and it appeared that the difference in energies was very small. Changing the location of the double bond had no observable effect on the adsorbed monolayers, and the isolated double bonds were not observed.
引用
收藏
页码:436 / 440
页数:5
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