On Some New Series of Biforked Mesogens

Abstract

Two series of biforked mesogens derived from 3,4-or 3,5-dialkoxybenzoic acids are described. The 3,5-derivatives exhibit only one hexagonal columnar mesophase, but the 3,4-derivatives display an interesting polymorphism such that phases with both columnar and lamellar mesomorphic order exist for the same sample. The relationship between this behaviour and the number and position of the substituents is discussed.