Hydrothermal synthesis and structural characterization of two 1-D and 2-D Dawson-based phosphotungstates

Abstract

Two new Dawson-based phosphotungstates (H 2en) 0.5H[Cu(en) 2(H 2O)] 2{[Cu(en) 2]( α 1-P 2W 17CuO 61)}·8H 2O ( 1) (en=ethylenediamine) and [4,4′-H 2bpy] 2{[Cu(4,4′-bpy) 3][Cu(4,4′-bpy) 4(H 2O) 2] 2[Cu(4,4′-bpy)][ α-P 2W 18O 62] 2}·6H 2O ( 2) (4,4′-bpy=4,4′-bipyridine) have been hydrothermally synthesized and structurally characterized. 1 crystallizes in the triclinic space group P−1 with a=11.7626(17), b=13.246(2), c=29.350(5) Å, α=87.355(5), β=79.583(5), γ=66.993(3)°, V=4138.3(11) Å 3, Z=2, GOF=1.089, R 1=0.0563 and w R 2=0.1505, whereas 2 belongs to the orthorhombic space group Iba2 with a=22.277(8), b=47.04(2), c=22.153(8) Å, V=23215(17) Å 3, Z=4, GOF=1.051, R 1=0.0627 and w R 2=0.1477. 1 consists of a 1-D linear chain structure constructed from monocopper II-substituted Dawson polyoxoanions, while 2 represents the first 2-D sheet-like structure with a (4,4)-connected topological net built up from plenary Dawson-type polyoxoanions and Cu II-4,4′-bpy complex cations in polyoxometalate chemistry.