Self-assembly of L-tryptophan on Cu(111) studied by low-temperature scanning tunneling microscopy  

作　　者：Qiang Xue Yajie Zhang Ruoning Li Chao Li Na Li Chenyang Yuan Shimin Hou Yongfeng Wang 

机构地区：[1]Key Laboratory for the Physics and Chemistry of Nanodevices,Department of Electronics,Peking University,Beijing 100871,China [2]Peking University Information Technology Institute(Tianjin Binhai),Tianjin 300450,China [3]Beijing Academy of Quantum Information Sciences,Beijing 100193,China

出　　处：《Chinese Chemical Letters》2019年第12期2355-2358,共4页中国化学快报（英文版）

基　　金：supported by the Ministry of Science and Technology (Nos.2018YFA0306003,2017YFA0205003);National Natural Science Foundation of China (No.21972002);supported by High-performance Computing Platform of Peking University

摘　　要：The self-assembly of L-tryptophan on Cu(111) is investigated by an ultrahigh vacuum scanning tunneling microscope(STM) at 4.4 K.When deposited onto the substrate at around 120 K with a coverage of 0.1 monolayer,molecular trimers,tetramers,hexamers,and chains coexist on Cu(111).Then almost all molecules self-assemble into chiral hexamers after being annealed at room temperature.When increasing molecular coverage to the full layer,a new type of chain is observed on the surface.Based on the high-resolution STM images at sub-molecular level,we suggest that the L-tryptophan molecules are present in neutral,zwitterionic or anionic states in these structures.The self-assembly of L-tryptophan on Cu(111) is investigated by an ultrahigh vacuum scanning tunneling microscope(STM) at 4.4 K.When deposited onto the substrate at around 120 K with a coverage of 0.1 monolayer,molecular trimers,tetramers,hexamers,and chains coexist on Cu(111).Then almost all molecules self-assemble into chiral hexamers after being annealed at room temperature.When increasing molecular coverage to the full layer,a new type of chain is observed on the surface.Based on the high-resolution STM images at sub-molecular level,we suggest that the L-tryptophan molecules are present in neutral,zwitterionic or anionic states in these structures.

关 键 词：Scanning tunneling microscopy TRYPTOPHAN SELF-ASSEMBLY Surface science HEXAMER 

分 类 号：TQ226.36[化学工程—有机化工]