Polymetal oxide materials

A polymetal oxide material of the formula III'

• CuMo.sub.A W.sub.B V.sub.C Nb.sub.D Ta.sub.E O.sub.Y .multidot.(H.sub.2 O).sub.F (III')
• where
• 1/(A+B+C+D+E) is from 0.7 to 1.3,
• F is from 0 to 1
• B+C+D+E is from>0 to 1 and
• Y is a number which is determined by the valency and frequency of the elements other than oxygen in III,
• whose structure type is selected from the group consisting of wolframite and distorted wolframite.

A polymetal oxide material of the formula IV

• Cu Mo.sub.A W.sub.B V.sub.C O.sub.Y (IV)
• where
• A+B+C is from 0.7 to 1.3,
• A, B and C are all>0, with the proviso that B+C.ltoreq.1, and
• Y is a number which is determined by the valency and frequency of the elements other than oxygen in (IV),
• whose structure type is selected from the group consisting of wolframite and distorted wolframite.

A polymetal oxide material of the formula V

• Cu Mo.sub.A W.sub.B O.sub.Y (V)
• where
• 1/A+B is from 0.7 to 1.3,
• A and B are all>0, with the proviso that B.ltoreq.1, and
• Y is a number which is determined by the valency and frequency of the elements other than oxygen in (VI),
• whose structure type is selected from the group consisting of wolframite and distorted wolframite.

A polymetal oxide material of the formula VI

• Cu Mo.sub.A V.sub.C O.sub.Y (VI)
• where
• 1/A+C is from 0.7 to 1.3,
• A and C are all >0, with the proviso that C.ltoreq.1, and
• Y is a number which is determined by the valency and frequency of the elements other than oxygen in (VI),
• whose structure type is selected from the group consisting of wolframite and distorted wolframite.