title: A Series of Lanthanide Metal-Organic Frameworks with Interesting Adjustable Photoluminescence Constructed by Helical Chains.
abstract: Based on the isonicotinic acid (HIN=pyridine-4-carboxylic acid), seven lanthanide metal-organic frameworks (MOFs) with the formula [Ln(IN)2 L] (Ln=Eu (1), Tb (2), Er (3), Dy (4), Ho (5), Gd (6), La (7), L=OCH2 CH2 OH) have been synthesized by mixing Ln2 O3 with HIN under solvothermal conditions, and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, infrared spectroscopy, and fluorescence spectroscopy. Crystal structural analysis shows that compounds 1-6 are isostructural, crystallize in a chiral space group P21 21 21 , whereas compound 7 crystallizes in space group C2/c. Nevertheless, they all consist of new intertwined chains. Simultaneously, on the basis of the above-mentioned compounds, we have realized a rational design strategy to form the doped Ln MOFs [(Eux Tb1-x )(IN)2 L] (x=0.35 (8), x=0.19 (9), x=0.06 (10)) by utilizing Tb(III) as the second "rare-earth metal". Interestingly, the photoluminescence of [(Eux Tb1-x )(IN)2 L] are not only adjustable by the ratios of Eu/Tb, but also temperature or excitation wavelength.
authors.affiliation: State Key Laboratory of Materials-Oriented, Chemical Engineering, Nanjing Tech University, Nanjing 210009 (P.R. China).
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Materials-Oriented, Chemical Engineering, Nanjing Tech University, Nanjing 210009 (P.R. China).
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Materials-Oriented, Chemical Engineering, Nanjing Tech University, Nanjing 210009 (P.R. China).
authors.forename: Gong Hao
authors.initials: GH
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Materials-Oriented, Chemical Engineering, Nanjing Tech University, Nanjing 210009 (P.R. China).
authors.forename: Shuai
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (P.R. China).
authors.forename: Ruiqing
authors.initials: R
authors.lastname: Fan
authors.affiliation: Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (P.R. China).
authors.forename: Yulin
authors.initials: Y
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Materials-Oriented, Chemical Engineering, Nanjing Tech University, Nanjing 210009 (P.R. China). yanxu@njtech.edu.cn.|State Key Laboratory of Coordination Chemistry, Nanjing Tech University, Nanjing 210093 (P.R. China). yanxu@njtech.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
keywords: X-ray diffraction; helical structures; lanthanides; luminescence; metal-organic frameworks