Two new supramolecular compounds with reversible skeleton structure changes during dehydration and rehydration: Synthesis and characterization
Autor: | Hong-Bo Liu, Xiu-Yan Wang, Ya-Guang Chen, Jun Ying |
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Rok vydání: | 2019 |
Předmět: |
Aqueous solution
010405 organic chemistry Chemistry Hydrogen bond Supramolecular chemistry Stacking 010402 general chemistry 01 natural sciences Fluorescence spectroscopy 0104 chemical sciences Inorganic Chemistry Crystallography Polyoxometalate Materials Chemistry Molecule Physical and Theoretical Chemistry Powder diffraction |
Zdroj: | Inorganica Chimica Acta. 493:14-19 |
ISSN: | 0020-1693 |
Popis: | Two novel supramolecular compounds of Keggin-type polyoxometalate (POM), [Cr(apca)2(H2O)2]4[KBW12O40]·9H2O (1), [Al(apca)2(H2O)2]8[SiW12O40]2·13H2O (2); apca = 3-aminopyrazine-2-carboxylic acid), were synthesized in aqueous solution and characterized by single-crystal X-ray diffraction technique, elemental analysis, TG analyses, IR, X-ray powder diffraction and fluorescence spectroscopy. In compound 1 [BW12O40]5− anion acting as octadentate ligand coordinates to two K ions through weak interaction, forming an infinite anionic chain extending along c–axis. The chains locate in the channels formed by stacking of the complex cations [M(apca)2(H2O)2]+. Hydrogen bonds combine the chains, cations and lattice water molecules forming a 3D framework. Besides the hydrogen bonds there exists π-π interaction between the complex cations. Compound 2 has a similar structure except without the K+ ion. They show a high proton conductivity of 1.70 × 10−3 S cm−1 and 9.30 × 10−3 S cm−1 at 77° C under 97% RH, respectively. Compound 1-2 showed reversible skeleton structure changes upon dehydration and rehydration, which had been established and monitored by X-ray powder diffraction. |
Databáze: | OpenAIRE |
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