Phase transitions among the rotator phases of the normal alkanes: A review

Although the rotator phases of the normal alkanes have been studied for the greater part of the century, it is only in the last two decades that the experimental and theoretical investigations of the structures and phase transitions of these systems have been advanced. This review article presents a comprehensive overview until this date of the theoretical developments and experimental studies in this subject. This article discusses the unified picture of the symmetry, structure and types of rotator phases of normal alkanes. This is followed by a discussion of the order parameters involved in the phase transitions. The application of the various theories to the description of the rotator phase transitions are reviewed comprehensively. The basic ideas of Landau theory and renormalization group theory and its applications to study these transitions are discussed. The current status of the study of the rotator phase transitions in the binary mixtures of alkanes including the nanoparticles and liquid crystal is outlined. A survey is given of existing computer simulation studies of the rotator phase transitions of the normal alkanes. A critical assessment of the experimental and theoretical investigations concerning the elastic properties of the rotator phases is made. (C) 2015 Elsevier B.V. All rights reserved.