Hydrothermal synthesis and characterization of a series of luminescent Zn(ii) and Cd(ii) coordination polymers with the new versatile multidentate ligand 1,3-di-(1,2,4-triazol-4-yl)benzene

• Published in: CrystEngComm 2013-01, Vol.15 (40), p.8097-8109
• Main Authors: Yang, Pan, Wu, Xiang Xia, Huo, Jian Zhong, Ding, Bin, Wang, Ying, Wang, XiuGuang
• Format: Article
• Language: English
• Subjects: Anion exchanging; Channels; Coordination polymers; Crystals; Helical; Ligands; Triazoles; Two dimensional
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/c3ce40946e

Used a newly designed multidentate benzene-based bis-triazole ligand 1,3-di-(1,2,4-triazol-4-yl)benzene (L), a series of luminescent Zn(ii) and Cd(ii) coordination polymers, namely, {[Zn( mu sub(2)-L) sub(2)(H sub(2)O) sub(2)].(SiF sub(6)).H sub(2)O} sub(n)1) , {[Cd( mu sub(2)-L) sub(2)(H sub(2)O) sub(2)].(SiF sub(6)).2H sub(2)O} sub(n)2 ), {[Zn( mu sub(2)-L)Br sub(2)] .H sub(2)O} sub(n)3), {[Cd( mu sub(2)-L) sub(2)(NC S) sub(2)].2H sub(2)O} sub(n)4), {[Cd( mu sub(2)-L)( mu sub(4)-L)](BF sub(4)) sub(2)} sub(n)5), {[Cd( mu sub(2)-L)( mu sub(4)-L)](ClO sub(4)) sub(2)} sub(n)6) and {[Cd sub(3)( mu sub(3)-L) sub(6)](NO sub(3)) sub(6)} sub(n)7) have been isolated under hydrothermal conditions. Both 1 and 2 present 1D double chain structures, which contain two kinds of different supramolecular channels. For 3, zinc(ii) ions are linked by L ligands and arranged into infinite right- or left-handed helical chains. 4 presents a 2D framework in which 1D right-handed and left-handed helical structures are interlinked viaCd(ii) centers as hinges. 5 and 6 respectively contain mu sub(2)- and mu sub(4)-L ligands in triazole-metal complexes. These mu sub(4)-L ligands link neighboring Cd(ii) centers forming a 2D network containing infinite {Cd-(trz) sub(2)-Cd} sub(n)hains, which is quite different from the 2D arrangement in 4. 7 presents a novel 3D porous MOF (porous metal-organic framework) containing triangular nano-porous channels with edges of 13.622 Aa, in which free NO sub(3) super(-) anions are located. Anion exchange experiments based on 7 also indicate that NO sub(3) super(-) anions are able to be exchanged with ClO sub(4) super(-) anions in the solid state. Both the dihedral angles (between two triazole rings or between triazole and aromatic benzene rings) for L are flexible and ultimately tune the coordination geometries in constructing various different coordination polymers. For 1-7 the comparison between powder X-ray diffraction (PXRD) and a simulated analysis from crystal data confirmed the pure crystal phases. Solid-state luminescent properties and thermal stabilities of 1-7 also have been determined.