The thermotropic cubic phase: a curious mesophase

The thermotropic cubic phase has been one of the more unexplored areas in liquid crystal research and has received considerable attention over the past 10 years. A review of the recent advances in the understanding of this curious mesophase is presented, giving special attention to the well-known 4′-n-alkoxy-3′-nitrobiphenyl-4-carboxylic acid homologues and related materials. It has now become clear that the formation of the thermotropic cubic phase is realized under a delicate balance of several competitive factors.