title: Penicillamine-protected Ag20nanoclusters and fluorescence chemosensing for trace detection of copper ions.
abstract: We report the synthesis of penicillamine-protected Ag20nanoclusters (NCs), with properties of high monodispersity, red fluorescence and water solubility. Full characterization of the Ag20NCs is addressed, along with first-principles optimization calculations, revealing the chemical composition and structure of the as-prepared Ag NCs within a molecular formula [Ag20(DPA)18-H]-. Moreover, natural bond orbital (NBO) analysis demonstrates the charge-transfer interactions between the ligand and Ag atoms, and helps in understanding the origins of fluorescence of Ag20NCs related to the ligand-to-metal charge transfer (LMCT) mechanism. Further, fluorescence chemosensing of the Ag20NCs is demonstrated for tracing copper ions with high sensitivity and selectivity in aqueous solution.
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China. zxluo@iccas.ac.cn hongbing.fu@iccas.ac.cn and Department of Chemistry, Huaibei Normal University, Huaibei, Anhui 235000, P. R. China.
authors.forename: Xianhu
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China. zxluo@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Weihua
authors.initials: W
authors.lastname: Ding
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China. zxluo@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Yishi
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China. zxluo@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Chenghui
authors.identifier: http://orcid.org/0000-0003-1440-0147
authors.initials: C
authors.lastname: Zeng
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China. zxluo@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Zhixun
authors.identifier: http://orcid.org/0000-0002-5752-1996
authors.initials: Z
authors.lastname: Luo
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China. zxluo@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Hongbing
authors.identifier: http://orcid.org/0000-0003-4528-189X
authors.initials: H
authors.lastname: Fu