NOVELTY - Producing metal mixed oxide powder comprises: atomizing a solution of a starting compound of a mixed oxide component with an atomizing gas to form an aerosol; introducing the aerosol into a flame; cooling the hot gases and the solid products; and removing the powders, where (a) metal carboxylates of 1-5C carboxylic acids and at least one starting compound per mixed oxide component are present in the solution, (b) the solution contains at least one 1-5C carboxylic acid anhydride, and (c) the sum of the portions of metal carboxylates in the solution based on a metal amounts to at least 20 wt.%.    USE - The antimony-tin mixed oxide powder or the dispersion is useful for: producing electrically-conductive paints and coatings, solar cells, infrared- and ultraviolet absorbers and in medical technology (claimed).    ADVANTAGE - The method: improves conductivity and dispersibility of the antimony-tin mixed oxide powder and the dispersion of it; allows the production of the metal mixed oxide powders on industrial scale; and shows homogeneous distribution of the mixed oxide components at the atomic level even at high content of metal since the solution used in the method has low viscosity even at high content of metals, and can be easily sprayed and thus improving the particle distribution. The dispersion containing the antimony-tin mixed oxide powder shows stability against sedimentation and gelation even at a storage of at least 2 months.    DETAILED DESCRIPTION - Producing metal mixed oxide powders comprises: atomizing a solution of a starting compound of a mixed oxide component with an atomizing gas to form an aerosol; introducing the aerosol into a flame formed by igniting a mixture of an oxygen containing gas and a fuel gas; cooling the hot gases and the solid products; and removing the metal mixed oxide powders, where (a) metal carboxylates of 1-5C carboxylic acids and at least one starting compound per mixed oxide component are present in the solution of starting compounds of the mixed oxide components, (b) the solution contains at least one 1-5C carboxylic acid anhydride, and (c) the sum of the portions of a metal carboxylate in the solution based on a metal amounts to at least 20 wt.%. INDEPENDENT CLAIMS are also included for:    (1) an antimony-tin mixed oxide powder, which exhibits a weight ratio of tin/antimony of 90:10-98:2, a Brunauer Emmett Teller surface area of 40-90 m2/g, presence of primary particles in the form of aggregate, which exhibits a homogeneous distribution of antimony and tin at a molecular level, a particle size distribution (d50) of less than 150 nm, a particle size distribution (d90) of less than 200 nm, a charge carrier density of at least 2.2 x 1018 cm-3, and a minimum specific resistance of less than 200 ohms x cm; and    (2) a dispersion containing the antimony-tin mixed oxide powder.