Crystal G phase of liquid crystalline material through inter molecular hydrogen bonding
1Faculty, Department of Physics, GITAM University Visakhapatnam (India).
2Centre for Liquid Crystal Research and Education & Faculty, Department of Physics, Acharya Nagarjuna University, Nagajuna Nagar (India).
DOI : http://dx.doi.org/10.13005/msri/050210
ABSTRACT:A systematic investigative work on thermotropic liquid crystals essentially on the long axis is developed by intermolecular hydrogen bonding with a mixture of mesogenic p-n-alkoxy benzoic acids together with non mesogenic hexyl-p-hydroxy benzoate. The thermodynamic behaviour of the liquid crystalline complexes were studied by polarizing optical microscope and realized by the differential scanning calorimetry. Element analysis, intermolecular hydrogen bonding and the structural determination of the liquid crystalline mixture were performed by the liquid chromatography mass spectrometer, infrared spectroscopy and proton nuclear magnetic resonance studies. The attributed studies by thermal analysis of the liquid crystalline mixture reveal dominant Crystal G phase with narrow span in the entire homologous series. The detailed study of IR in both the solid and liquid states between the groups convinced the strong inter molecular hydrogen bond between the groups and its destruction in solution. Further the influence of the family of benzoates n-phydroxy benzoates on the p-n-alkoxy benzoic acids is realized by comparative study of the present complexes with the reported studies.
KEYWORDS:nABA; HHB; intermolecular hydrogen bonding; crystal G phase




