Cholesteric blue phases of the cholesteryln-alkanoates

The structures of the blue phases are investigated in the homologous series of cholesteryl $n$-alkanoates by the examination of Bragg reflections. Through the use of the selection rules developed by Hornreich and Shtrikman, evidence is presented for the first time for the existence of a body-centered-cubic structure of $O^5$ symmetry. The first direct demonstration by this technique for the existence of simple cubic structures is also given.