Description

• Title:
  How much do coulombic interactions stabilize a mesophase? Ion pair and non-ionic binary isosteric derivatives of monocarbaborates and carboranes
• Creator:
  Jankowiak, Aleksandra;
  Sivaramamoorthy, Ajan;
  Pociecha, Damian;
  Kaszyński, Piotr
• Contributor:
  Vanderbilt Universit, Department of Chemistry;
  University of Warsaw, Department of Chemistry;
  University of Łódź, Faculty of Chemistry;
  piotr.kaszynski@vanderbilt.edu
• Description:
  Replacement of the B− atom in the monocarbaborate anion, 1[10] or 1[12], and the N^+ atom in the pyridinium cation [Pyr] of a liquid crystalline ion pair with C atoms leads to an isoelectronic and isosteric non-ionic binary liquid crystalline mixture of carborane (2[10] or 2[12]) and benzene ([Ph]) derivatives lacking coulombic interactions. A comparison of mesogenic properties of ion pairs, 1[10]c–[Pyr]c and 1[12]c–[Pyr]c, with their analogous non-ionic mixtures, 2[10]c–[Ph]c and 2[12]c–[Ph]c, shows a 181 K higher clearing temperature, T_c, for the ion pair. This corresponds to a DFT-calculated difference in association energy ΔΔH_a = 24.5 kcal mol^{−1} in a typical dielectric medium (ε = 2.5). Pure compounds and binary mixtures were characterized using thermal, optical, and XRD methods.;
  This work was supported by the NSF grant DMR-1207585
• Object availability:
  free access
• Rights:
  Uznanie autorstwa 3.0 Polska;
  http://creativecommons.org/licenses/by/3.0/pl
• Date:
  2016.03.31;
  2014
• Type:
  Article
• Language:
  English
• Format:
  application/pdf
• Publisher:
  Royal Society of Chemistry
• Relation:
  RSC Advances;96;
  4
• Identifier: http://hdl.handle.net/11089/17602 ;
  10.1039/C4RA06502F
• Data provider:
  Repozytorium Uniwersytetu Łódzkiego
• Can I use it?:
  check license
• Type:
  image