Disorder and pseudo-symmetry in octakis(trivinylsilyl)octasilicate.

Octakis(trivinylsilyl)octasilicate was prepared by capping octaspherosilicate cubes, [Si(8)O(20)](8-), with trivinylsilyl groups in methanol solution. Crystals grown from CCl(4) crystallize in the tetragonal space group I4(1). Systematic absences are consistent with the space group I4(1)/amd, although the R(int) values clearly indicate 4/m rather than 4/mmm Laue symmetry.