Structures, magnetic and catalytic properties of three sandwich-type silicotungstates containing tetranuclear copper(ii)clusters†
Abstract
Three sandwich-type silicotungstates, formulated as [Cu4(H2O)2(SiW9O34)2]·12NH4·22H2O (1), [Cu4(H2O)2(SiW9O34)2]·12NH4·11H2O (2) and {[Cu(NH3)4]2[Cu(H2O)4][Cu4(H2O)2(SiW9O34)2]} 2[Cu(NH3)4(H2O)]·2NH4·6H2O (3), were synthesized by microwave irradiation and