Discovery of two Na+-centered Silverton-type polyoxometalates {NaM12O42} (M = Mo, W)

Two new Silverton archetypes [NaM₁₂O₄₂]¹¹⁻ were demonstrated in the POMs Na₃[NaM₁₂O₄₂(Ru(DMSO)₃)₄]·13H₂O (M = Mo, W). The alkali metal Na⁺ ion incubated as a heteroatom is reported for the first time in POMs and further certified by ²³Na NMR.