Mesophase formation in a system of top-shaped hard molecules

Density functional theory and Monte Carlo simulation

Daniel De Las Heras, S. Varga, Franz J. Vesely

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

We present the phase diagram of a system of mesogenic top-shaped molecules based on the Parsons-Lee density functional theory and Monte Carlo simulation. The molecules are modeled as a hard spherocylinder with a hard sphere embedded in its center. The stability of five different phases is studied, namely, isotropic, nematic, smectic A, smectic C, and columnar phases. The positionally ordered phases are investigated only for the case of parallel alignment. It is found that the central spherical unit destabilizes the nematic with respect to the isotropic phase, while increasing the length of the cylinder has the opposite effect. Also, the central hard sphere has a strong destabilizing effect on the smectic A phase, due the inefficient packing of the molecules into layers. For large hard sphere units the smectic A phase is completely replaced by a smectic C structure. The columnar phase is first stabilized with increasing diameter of the central unit, but for very large hard sphere units it becomes less stable again. The density functional results are in good agreement with the simulations.

Original languageEnglish
Article number214902
JournalThe Journal of Chemical Physics
Volume134
Issue number21
DOIs
Publication statusPublished - Jun 7 2011

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Density functional theory
density functional theory
Molecules
molecules
simulation
Phase diagrams
alignment
phase diagrams
Monte Carlo simulation

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this

Mesophase formation in a system of top-shaped hard molecules : Density functional theory and Monte Carlo simulation. / De Las Heras, Daniel; Varga, S.; Vesely, Franz J.

In: The Journal of Chemical Physics, Vol. 134, No. 21, 214902, 07.06.2011.

Research output: Contribution to journalArticle

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