Yitamben E N, Clayborne A, Darling Seth B, Guisinger N P
Center for Nanoscale Materials (CNM), Argonne National Laboratory, Argonne, IL 60439, USA.
Nanotechnology. 2015 Jun 12;26(23):235604. doi: 10.1088/0957-4484/26/23/235604. Epub 2015 May 21.
The present article investigates the adsorption and molecular orientation of L-Tryptophan, which is both an essential amino acid important for protein synthesis and of particular interest for the development of chiral molecular electronics and biocompatible processes and devices, on Cu(111) using scanning tunneling microscopy and spectroscopy at 55 K and at room temperature. The arrangement of chemisorbed L-Tryptophan on the copper surface varies with both temperature and surface coverage. At low coverage, small clusters form on the surface irrespective of temperature, while at high coverage an ordered chain structure emerges at room temperature, and a tightly packed structure forms a molecular labyrinth at low temperature. The dominating superstructure of the adsorbates arises from intermolecular hydrogen bonding, and π-bonding interactions between the indole groups of neighboring molecules and the Cu surface.
本文利用扫描隧道显微镜和光谱技术，在55K和室温下研究了L-色氨酸在Cu(111)表面的吸附和分子取向。L-色氨酸既是蛋白质合成所必需的氨基酸，也是手性分子电子学以及生物相容过程和器件发展中特别受关注的物质。化学吸附在铜表面的L-色氨酸的排列随温度和表面覆盖率而变化。在低覆盖率时，无论温度如何，表面都会形成小簇；而在高覆盖率时，室温下会出现有序链结构，低温下则会形成紧密堆积结构，形成分子迷宫。吸附质的主要超结构源于分子间氢键以及相邻分子的吲哚基团与铜表面之间的π键相互作用。
