title: Temperature-dependent assemblies from a 2-D triple-stranded meso-helical layer to a 3-D chain-layer metal-organic framework.
abstract: Two different crystal forms, namely {[Dy2(mpda)3(H2O)2]·H2O}n (1) and [Dy2(mpda)3(H2O)4]n (2), were obtained from the reaction of multidentate 2,6-dimethylpyridine-3,5-dicarboxylic acid (H2mpda) with Dy2O3 at different temperatures. Structural analysis reveals that compound 1 is a 2-D triple-stranded meso-helical layer, and 2 a 3-D chain-layer framework. The fluorescent measure shows that compound 1 is a promising luminescent probe for various metals with a remarkable “on–off” switch of emission, mainly deriving from many pairs of inversely arranged 4-aza bowl-like crown ethers distributed in the 2-D helical plane. Moreover, compound 1 presents noticeable hydrogen-sorption at medium pressure.
authors.affiliation: Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University, Guangzhou 510006, PR China.
authors.forename: Hong-Guang
authors.initials: HG
authors.lastname: Jin
authors.forename: Xu-Jia
authors.initials: XJ
authors.lastname: Hong
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yuan-Zhao
authors.initials: YZ
authors.lastname: Yan
authors.forename: Yi-Ting
authors.initials: YT
authors.lastname: Liu
authors.forename: Shi-Hai
authors.initials: SH
authors.lastname: Xu
authors.forename: Yue-Peng
authors.initials: YP
authors.lastname: Cai
mesh_terms: D043844:Crown Ethers / Q000737:chemistry; D003460:Crystallization; D018360:Crystallography, X-Ray; D003998:Dicarboxylic Acids / Q000737:chemistry*; D004419:Dysprosium / Q000737:chemistry; D049408:Luminescent Agents / Q000737:chemistry*; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D013696:Temperature
chemical_list: D043844:Crown Ethers; D003998:Dicarboxylic Acids; D049408:Luminescent Agents; D009942:Organometallic Compounds; D011725:Pyridines; D004419:Dysprosium; C030582:dysprosium oxide