Deviations from 1:1 compositions in self-assembled monolayers formed from adsorption of asymmetric dialkyl disulfides on gold

被引：93

作者：

Heister, K

Allara, DL ^{[1
]}

Bahnck, K

Frey, S

Zharnikov, M

Grunze, M

机构：

[1] Penn State Univ, Dept Chem, University Pk, PA 16802 USA

[2] Penn State Univ, Dept Mat Sci, University Pk, PA 16802 USA

[3] Univ Heidelberg, D-69120 Heidelberg, Germany

来源：

LANGMUIR | 1999年 / 15卷 / 17期

关键词：

D O I：

10.1021/la9902385

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Alkanethiolate monolayers on polycrystalline gold, formed by typical solution self-assembly conditions with immersion in dilute ethanolic solution of asymmetric dialkyl disulfides CH3(CH2)(n-1)SS(CH2)(15)CH3 (n = 4, 8, 12), were found to consist predominately of CH3(CH2)(15)S- moieties. This observation shows that large deviations from expected 1:1 compositions can occur. The data support an exchange mechanism involving dissociative chemisorption of the S-S moiety and a subsequent replacement of the shol ter chains by the longer ones via short chain disulfide or thiolate desorption and readsorption of mixed chain length disulfide. The efficiency of the substitution process increases with increasing length difference of the hydrocarbon chains in the respective disulfides.

引用

页码：5440 / 5443

页数：4

共 28 条

[1] Identification of transitions into Rydberg states in the X-ray absorption spectra of condensed long-chain alkanes [J].