Formation of Unconventional Stoichiometric Na–Cl Magic‐Number Nanoclusters and 2D Assembly on Ir(111). Issue 3 (27th January 2022)

• Record Type: Journal Article
• Authors: Tan, Xin; Pan, Jinliang; Wu, Yangfan; Xu, Peng; Sun, Luye; Hu, Kui; Qiu, Xia; Li, Menglei; Liu, Mengxi; Ma, Donglin; Qiu, Xiaohui
• Is Part Of: Small methods. Volume 6:Issue 3(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-27
• Subjects: magic‐number nanoclusters -- noncontact atomic force microscopy -- scanning tunneling microscopy -- sodium chloride -- unconventional stoichiometries; Nanotechnology -- Methodology -- Periodicals; Nanotechnology -- Periodicals; Periodicals; 620.5028
• DOI: 10.1002/smtd.202101252
• Languages: English
• ISSNs: 2366-9608

Abstract

Abstract: Sodium chlorides in non‐1:1 stoichiometry are counterintuitive but recently their existence has been found under the high pressure condition or in the confined space between graphene sheets. Here the direct observation of the formation of Na3 Cl nanoclusters, a stable magic‐number structure, is reported on an Ir(111) surface using scanning tunneling microscopy and noncontact atomic force microscopy. The stability of Na3 Cl nanoclusters in the free and adsorbed state is corroborated by density functional theory calculations. It is also found that a density of nanoclusters together with Cl adatoms may further aggregate and self‐assemble into a Na3 Cl4 monolayer, forming a novel metastable phase of NaCl(111) with a honeycomb lattice. Further calculations suggest that charge transfer between the polar nanoclusters and the metal substrate stabilizes NaCl of non‐1:1 stoichiometry. The work exhibits the possibility of exploring unconventional ionic crystals on the surface with atomically precise control of structure and composition. Abstract : This work demonstrates that magic‐number Na3 Cl and 2D assembly of Na3 Cl4 exist on an Ir(111) surface at room temperature. The 2D magic cluster assembly provides an opportunity to tailor the surface state electron gases via atomic‐scale local gating and periodic templating, enabling a further exploration of exotic quantum states on metallic surfaces.