43. Thote, Amol J.; Gupta, Ram B.. Hydrogen-Bonding Effects in Liquid Crystals for Application to LCDs. Industrial & Engineering Chemistry Research (2003), 42(6), 1129-1136.
Hydrogen bonding plays an important role in the performance of liq. crystal displays (LCDs) by controlling the soly. and dissoln. stability of dichroic dyes in the liq. crystal medium, for guest-host type LCDs. The hydrogen-bonding behaviors of 4-pentyl-4'-cyanobiphenyl (5CB) (liq. crystal), benzonitrile, and acetonitrile, with 1-hexanol in CCl4 were studied using FTIR spectroscopy, equations of state, and ab initio calcns. In all three mixts., the -OH group acts as a hydrogen-bond donor, and the -CN group acts as a hydrogen-bond acceptor. On the basis of FTIR anal., the enthalpy of hydrogen-bond formation is obsd. to be -14.7 kJ/mol for 1-hexanol/acetonitrile, -5.4 kJ/mol for 1-hexanol/benzonitrile, and -4.6 kJ/mol for 1-hexanol/5CB. The entropy of hydrogen-bond formation is more favorable for 1-hexanol/5CB than for 1-hexanol/acetonitrile or 1-hexanol/benzonitrile. Trends in the spectroscopic results agree with ab initio calcns. Lattice fluid hydrogen-bonding parameters also were obtained from the spectroscopic data.