Investigations to calcine these mesoporous materials are still in progress. So far, we can say that the calcination process which works for the silica mesophases (heating the samples first in pure nitrogen and then in pure oxygen with slow heating rates of 1 K min-' up to 550 "C) has not led to tungsten and antimony oxide mesostructured materials. The framework of these materials collapsed during this calcination process probably due to a reduction of the framework either by a redox process with the template (for the tungsten oxide materials) or an intrinsic instability of the higher oxidation state (for the antimony(V) oxide materials) at high temperatures. At the moment we are examining more gentle chemical and physical ways to remove the surfactants from the mesostructured materials without destroying the framework.