Title:	Synthesis and mesomorphic properties of nonsymmetric liquid crystalline dimers containing azobenzene groups
Authors:	Rahman, Md Lutfor Asik, Jahimin Kumar, Sandeep Silong, Sidik Rahman, M.Z.A.
Keywords:	mesophase azobenzene nonsymmetric dimers cis-trans isomers nematic smectic
Issue Date:	Mar-2009
Publisher:	Taylor & Francis
Citation:	Phase Transitions, 2009, Vol.82, p228
Abstract:	Four novel nonsymmetric dimers containing azobenzene mesogenic groups were synthesized. The nonsymmetric dimers compounds namely, ethyl 4-[(4-lcub4-(4-((4-nitrophenyl)diazenyl)phenoxy)alkyloxyrcubphenyl)diazenyl]benzoate were obtained from the alkylation of ethyl 4-[(4-(4-bromoalkyloxy)phenyl)diazenyl]benzoate with 4-[(4-nitrophenyl)diazenyl]phenol. The mesomorphic properties of the compounds were determined by DSC and polarizing optical microscopy. The first member of the series was nonliquid crystalline while all other homologues display nematic and smectic A phases. The trans-azobenzene groups of the dimers display a high-intensity π-π* transition at about 365 nm and a low-intensity n-π* transition at around 465 nm, therefore, photochromism can be achieved by the introduction of the azo linkage to the dimeric liquid crystalline molecules.
Description:	Restricted Access.
URI:	http://hdl.handle.net/2289/3805
ISSN:	E-ISSN: 1029-0338 P-ISSN: 0141-1594
Alternative Location:	http://dx.doi.org/10.1080/01411590802642406
Copyright:	2009 Taylor & Francis
Appears in Collections:	Research Papers (SCM)

Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.