Synthesis and characterization of one- to three-dimensional compounds composed of paradodecatungstate-B cluster and transition metals as linkers

Abstract

Three new extended frameworks built from paratungstate and transition metals have been synthesized and characterized. In the compound Na 8[{Cd (H 2O) 2}(H 2W 12O 42)]·32H 2O ( 1), two neighboring paratungstate-B ions [H 2W 12O 42] 10− are linked by [Cd(H 2O) 2] 2+ units, leading to the formation of infinite one-dimensional (1D) anion chain [{Cd(H 2O) 2}(H 2W 12O 42)] n 8 n− . The anion [{Co(H 2O) 3}{Co(H 2O) 4}(H 2W 12O 42)] n 6 n− of the compound Na 6[{Co(H 2O) 3}{Co(H 2O) 4}(H 2W 12O 42)]·29H 2O ( 2) shows a layer-like (2D) structure in which paratungstate-B units are linked by CoO 6 octahedra, while the anion [{Co(H 2O) 3} 3(H 2W 12O 42)] n 4 n− of the compound (H 3O +) 3[{Na(H 2O) 4}{Co(H 2O) 4} 3(H 2W 12O 42)]·24.5H 2O ( 3) is a three-dimensional (3D) anionic polymer that consists of paratungstate-B units linked by CoO 6 octahedra. Compound 3 can reversibly adsorb and desorb water molecules leading to the color reversibly change from pink to violet. The preliminary magnetic measurement and electrochemical properties of compounds are performed. The crystal structure of unexpected product Na 4[NiW 6O 24H 6]·13H 2O ( 4) is described here for the rare report of crystal structure information on the Anderson-type polyoxotungstate which has nickel as a heteroatom.