Syntheses, Structures and Magnetic Properties of Three New Extended Iron‐containing Heteropolytungstates

Three new extended iron‐containing heteropolytungstates were synthesized and structurally characterized: K6[{FeII(H2O)4}2(H2W12O42)]·15H2O (1), Na5[{Fe(H2O)3}2{Fe(H2O)4}0.5(H2W12O42)]·30H2O (2) and (H3O)+2[{Fe(H2O)4Fe(H2O)3}2(H2W12O42)]·20H2O (3). 1 and 3 crystallize in the monoclinic system, space group P21/n with a = 14.9967(5), b = 10.3872(3), c = 18.8237(6)Å, β = 93.407(1)°, V = 2927.1(2)Å3 and Dc = 4.151 g cm—3 for 1, and space group P21/c with a = 12.1794(4), b = 22.4938(4), c = 11.6941(3) Å, β = 105.731(2)°, V = 3083.7(1) Å3, and Dc = 4.043 g cm—3 for 3. 2 is triclinic, space group P1¯, with a = 12.121(2), b = 12.426(3), c = 13.247(3)Å, α = 68.33(3), β = 71.33(3), γ = 71.44(3)°, V = 1710.7(6)Å3 and Dc = 3.735 g cm—3. In all cases, the structures are based on paradodecatungstate polyoxoanions, which are linked by iron ions into chains, layers and a three‐dimensional structure for 1, 2 and 3, respectively.