| abstract |
Abstract of the Disclosure: Multimetal oxide compositions of the formula I [X1aX2bOx]p [X3cX4dX5eX6fX7gX2hOy]q (I) where X1 is bismuth, tellurium, antimony, tin and/or copper, X2 is molybdenum and/or tungsten, X3 is an alkali metal, thallium and/or samarium, X4 is an alkaline earth metal, nickel, cobalt, copper, manganese, zinc, tin, cadmium and/or mercury X5 is iron, chromium, cerium and/or vanadium, X6 is phosphorus, arsenic, boron and/or antimony, X7 is a rare-earth metal, titanium, zirconium, niobium, tantalum, rhenium, ruthenium, rhodium, silver, gold, aluminum, gallium, indium, silicon, germanium, lead, thorium and/or uranium, a is from 0.01 to 8, b is from 0.1 to 30, c is from 0 to 4, d is from 0 to 20, e is from 0 to 20, f is from 0 to 6, g is from 0 to 15, h is from 8 to 16, x and y are numbers determined by the valency and fre-quency of the elements in I other than oxygen, and p and q are numbers whose ratio p/q is from 0.1 to 10, containing three-dimensional regions with a chemical composition X1aX2bOx which are delimited from their local environment due to their chemical composition which is different from their local environment, and whose maximum diameter is from 1 to 25 µm. |