Molecular approach to phase transitions in a calamitic ester substituted aroylhydrazone liquid crystal

Abstract

Temperature dependent Raman and X‐ray diffraction studies of a calamitic ester substituted aryolhydrazone liquid crystal (LC) system; N‐[4‐(4ʹ‐decyloxy)benzoyloxy benzylidene]‐Nʹ‐[4ʹ‐decyloxybenzoyl]hydrazine (DB2H) have been performed to investigate the molecular arrangement and intermolecular interaction environment in LC phase. X‐ray diffraction study with the help of density functional theoretical study gives the information of molecular tilt angle in SmC layer. Prominent Raman signatures of crystal I → crystal II, crystal II → SmC and SmC → Isotropic phase transitions were identified in terms of changes in peak position and linewidth as well as Raman intensity. Analysis of Raman marker bands gives evidence of residual intermolecular hydrogen bonds between amide groups responsible for tilting arrangement in SmC phase. Copyright © 2016 John Wiley & Sons, Ltd.