Abstract:
Sphere growth experiments have been performed on a series of distorted beta-K2SO4- type structures, all having a modulated crystal structure. An inventory of all satellite forms occurring was made. The stabilities of these forms were found to be clearly dependent on the length of the modulation wave vector. The results were compared with a connected net analysis and calculations on surface energies in a (1 + 1)-dimensional modulated crystal model. A qualitatively good agreement between experiments and theory was found. The selection rules of the superspace group were shown to be relevant.