Premium
Quinquephenyl: The Simplest Rigid‐Rod‐Like Nematic Liquid Crystal, or is it? An Atomistic Simulation
Author(s) -
Olivier Yoann,
Muccioli Luca,
Zani Claudio
Publication year - 2014
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201301126
Subject(s) - thermotropic crystal , liquid crystal , mesogen , isotropy , phase (matter) , molecular dynamics , phase transition , materials science , chemical physics , crystallography , chemistry , condensed matter physics , thermodynamics , liquid crystalline , computational chemistry , physics , optics , organic chemistry
We have performed an atomistic molecular‐dynamics study on the molecular organization and liquid‐crystalline properties of quinquephenyl (P5), a prototypical mesogen that is of interest for organic electronics. The thermotropic behavior reveals different mesophases. When cooling down from the isotropic phase, a transition to nematic (≈715 K) is found, then a smectic S A (≈657 K) and another smectic, ${S_{\rm{A}}^{\rm{X}} }$ (≈642 K), before a crystalline phase is recovered (≈617 K). This phase sequence is compared with experimental findings. The different phases are described in terms of their molecular organization, orientational and positional order parameters, and pair distribution functions, as well as of their dynamics properties. In particular, the smectic phases that have not yet been characterized experimentally are discussed. By analyzing the effective shape of P5, it is concluded that its internal torsions and bending make it less rigid than could be expected.