Adsorption Configuration of Serine on Ge(100): Competition between the Hydroxymethyl and Carboxyl Groups of Serine During the Adsorption Reaction
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- 作者：Sena Yang ; Yaewon Kim ; Sunmin Park ; Heesun Lim ; Hangil Lee
- 刊名：Journal of Physical Chemistry C
- 出版年：2011
- 出版时间：May 12, 2011
- 年：2011
- 卷：115
- 期：18
- 页码：9131-9135
- 全文大小：823K
- 年卷期：v.115,no.18(May 12, 2011)
- ISSN：1932-7455
文摘
We investigated the adsorption structures of serine on a Ge(100) surface by core-level photoemission spectroscopy (CLPES) in conjunction with density functional theory (DFT) calculations. The adsorption energies calculated using DFT methods suggested that four of six adsorption structures were plausible. These structures were the O鈥揌 dissociated-N dative bonded structure, the O鈥揌 dissociation bonded structure, the Om鈥揌 dissociated-N dative bonded structure, and the Om鈥揌 dissociation bonded structure (where Om indicates the hydroxymethyl oxygen). These structures are equally likely, according to the adsorption energies alone. The core-level C 1s, N 1s, and O 1s CLPES spectra confirmed that the carboxyl oxygen competed more strongly with the hydroxymethyl oxygen during the adsorption reaction, thereby favoring formation of the O鈥揌 dissociated-N dative bonded and O鈥揌 dissociation bonded structures at 0.30 and 0.60 ML, respectively. The experimental results were corroborated theoretically by calculating the reaction pathways leading to the two adsorption geometries. The reaction pathways indicated that the O鈥揌 dissociated-N dative bonded structure is the major product of serine adsorption on Ge(100) due to comparably stable adsorption energy.