Interaction of 2,2,6,6-tetramethyl-3,5-heptanedione with the Si(100)-2 x 1 surface: Scanning tunneling microscopy and density functional theory study

被引：13

作者：

Skliar, D. B. ^{[1
]}

Gelmi, C. ^{[1
]}

Ogunnaike, T. ^{[1
]}

Willis, B. G. ^{[1
]}

机构：

[1] Univ Delaware, Dept Chem Engn, Newark, DE 19716 USA

来源：

SURFACE SCIENCE | 2007年 / 601卷 / 14期

基金：

美国国家科学基金会;

关键词：

Si(100); scanning tunneling microscopy; density functional calculations; temperature programmed desorption;

D O I：

10.1016/j.susc.2007.04.194

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Room temperature adsorption and reaction of 2,2,6,6-tetramethyl-3,5-heptanedione (dpmH) on the Si(1 0 0)-2 x 1 surface has been studied with ultra-high vacuum scanning tunneling microscopy (UHV-STM) and temperature programmed desorption JPD). The molecule is found to chemisorb as a mixture of at least five distinct species. Density functional theory (DFT) was used to calculate the structures and adsorption energies of 12 possible addition products. Unique bonding assignments for each experimental feature are proposed by consideration of a common intermediate reaction network, and a comparison of possible reaction pathways leading to the final products. These assignments are: OH inter-dimer dissociation, OH intra-dimer dissociation, 1,5 intra-dimer addition, 1,5 inter-dimer addition, and intra-dimer [2 + 2]C=O addition with OH dissociation on an adjacent dimer. TPD and STM results show that the molecule dissociates completely upon annealing to 700 degrees C with formation of the c(4 x 4) phase at low exposures, and SiC islands for exposures exceeding 0.15 L. (C) 2007 Elsevier B.V. All rights reserved.

引用

页码：2887 / 2895

页数：9

共 71 条

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