The thermal stability and molecular structural changes of a intermolecular hydrogen bonded liquid crystal compound

In order to investigate the thermal stability of the intermolecular hydrogen bonding and the molecular structure changes during the phase transition process, we studied liquid crystal compound DBS:BD:DBS induced by intermolecular hydrogen bonding between trans-butene diacid (proton donor) and 4-(2,3,4-tridecyloxybenzoyloxy)-4'-stilbazoles (proton acceptor) using the temperature-dependent FT-IR and FT-Raman spectroscopy. The results show that the intermolecular hydrogen bonding is stable in the liquid crystalline phase but becomes slightly decompositive when temperature is higher than its clearing point. As the temperature increasing, the number of the gauche conformation is also increasing, when it is coming to the isotropic phase, the alkyl chain is in disorder state. (C) 2000 Elsevier Science B.V. All rights reserved.