There are many structures of rare earth-containing heteropoly compounds including Weakley
Silverton
Keggin and Dawson structure et al.In these structures
Keggin and Dawson structure are studied more than other structures.Some research indicted that [Ln(β2-SiW11O39)2]13-exhibit two different configurations.Large Ln3+ ions appear to favor an(R
R)(or(S
S)) configuration(point group C2) of the Keggin units
with an increasing amount of(R
S)(or(S
R)) configuration(point group C1) found in the solid state as the Ln3+ ion decreases in size.According to researches Ln3+ and the Dawson units can be formed compounds with different structures such as 1∶1
2∶2
1∶2
2∶1
3∶1 or 3∶2 in different reaction conditions.The hot research area is to synthesize novel heteropoly compounds consisting of organic group by lanthanum ligand.The rare earth-containing heteropoly compounds have inhibiting effect on HIV
influenza virus
hepatitis B virus
and also have good anti-tumor and inhibitory effect.The researches on anti-HIV
anti-influenza virus and anti-tumor are more than others.