U. Kortz et Mt. Pope, POLYOXOMETALATE-DIPHOSPHATE COMPLEXES .4. STRUCTURE OF NA-4[(O3PCHN(CH3)(2)PO3)W2O6]CENTER-DOT-11H(2)O, Inorganic chemistry, 34(14), 1995, pp. 3848-3850
Structural analysis of the sodium salt of ([(O3PCHN(CH3)(2)PO3)W2O6](4
-))infinity revealed a novel polymeric heteropolyanion of tungsten whi
ch is composed of negatively-charged chains where [(O3PCHN(CH3)(2)PO3)
W2O6](4-) (I) is the repeat unit. I comprises two corner-shared WO6 oc
tahedra and one (dimethylamino)methylenediphosphonate hetero group. In
the polymer, the monomeric units are linked to give an undulating cha
in in which the hetero groups alternate up and down. In each chain the
tungsten atoms and their bridging oxygens can be viewed as the planar
backbone describing a sine wave.