Abstract: A method for the surface modification of particles containing oxidic compounds of metals and/or semimetals M having M-O—H groups on the surface thereof. The particles are contacted with silicon-halogen compounds under conditions such that the M-O—H groups react with the silicon-halogen compounds. The particles thus produced can have Si—OH, Si-Halogen, and/or Si-Organic Radical groups in a density of at least two such groups per nm2 surface and/or have at least four carbon atoms corresponding to the Si-Organic Radical groups per nm2 of surface.