Molecular Structure and Packing Analysis of Two Nematogenic Fluoro-Phenyl Compounds in the Crystalline Phase

  • Sripada Haldar
  • Pradip Kumar Mandal
  • Wolfgang Haase
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 340)

Abstract

The crystal and molecular structures of two nematogenic compounds 4′-(3, 4-difluoro-phenyl)-4-propyl-bicyclohexyl(3ccp-ff) and 4′-(3,4,5-trifluoro-phenyl)-4-propyl-bicyclohexyl(3ccp-fff) have been determined by direct methods using single crystal X-ray diffraction data. The compounds (C21 H30 F2) and (C21H29F3) crystallize in the monoclinic system with the space group P21/n and Z = 4 and in the triclinic system with the space group \( {\text{P}}\overline{1} \) and Z = 2 respectively. The fluorine atoms are in the plane of phenyl ring. Both the cyclohexyl groups are found to be in chair conformation. Parallel imbricated mode of packing of the molecules are found in the crystalline state which is precursor to the nematic phase. Several van der Waals interactions are observed between the neighbouring molecules. Results of crystal structure have been compared with that obtained from molecular modelling.

Keywords

Nematogen Fluorophenyl X-ray diffraction Imbricated mode of packing Molecular association Molecular modelling 

Notes

Acknowledgments

The authors would like to thank Dr. E. Poetsch, Merck, Germany for supplying the compounds. This work has been supported by the Research Project of North bengal University.

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Copyright information

© Springer India 2015

Authors and Affiliations

  • Sripada Haldar
    • 1
  • Pradip Kumar Mandal
    • 1
  • Wolfgang Haase
    • 2
  1. 1.Department of PhysicsNorth Bengal UniversitySiliguriIndia
  2. 2.Institute of Physical ChemistryDarmstadt University of TechnologyDarmstadtGermany

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