甘氨酸在Cu(001)表面的吸附结构

结合低能电子衍射(LEED)及其消失斑点规律和扫描隧道显微镜(STM)手段确定了室温下甘氨酸在Cu(001)表面能形成c(2×4)和两种(2×4)吸附结构((2×4)₁和(2×4)₂)，并推断出在两种(2×4)结构单胞中两甘氨酸分子的羧基相对于衬底的吸附取向一致，而它们的氨基则不同.实验中还观察到c(2×4)与(2×4)₂结构能相互转变成窄条相互穿插共存，这说明几种吸附结构能量相近.关键词：

ADSORPTION STRUCTURES OF GLYCINE ON Cu(001)

Low-energy electron diffraction(LEED) and scanning tunneling microscopy(STM) have been used to determine the adsorption structures of glycine on the Cu(001) surface at room temperature.Glycine can adsorb on Cu(001) to form three ordered structures:one c(2×4) and two of the type of (2×4) structures,i.e.,(2×4)₁ and (2×4)₂.According to the molecular resolution STM images and the rule about missing spots in LEED,it is deduced that the carboxylic groups of the two molecules in a unit cell of any of the two (2×4) structures have the same adsorption geometry with respect to the substrate,while the amino groups do not.The three adsorption structures are expected to have almost the same energy,as the narrow stripped domains of them may co-exist and the c(2×4) and (2×4)₂ domains sometimes may even change from one to another.