NDLI: Thermal and photoinduced liquid crystalline phase transitions with a rod–disc alternative change in the molecular shape

Content Provider	Royal Society of Chemistry (RSC)
Author	Ishiguro, Hisato Uchida, Kingo Shimizu, Yo Tanaka, Daisuke
Copyright Year	2012
Abstract	A triphenylene derivative which has six 4-tetradecyloxyazobenzene units connected with propylene–ester linkages (1) was synthesised to study the liquid crystalline phase transitions in both thermotropic and photo-induced manners. It was found that 1 exhibits smectic A (SmA) and rectangular columnar (Colr) mesophases in an enantiotropic way. This means that 1 can behave as both rod- and disc-like molecules depending on the thermal condition. To the best of our knowledge, this is the first case in thermotropic liquid crystals where one compound exhibits both calamitic and discotic mesomorphism with the change of molecular shape in anisotropy. Under the photo-irradiation at 365 nm of wavelength which induces a photoisomerisation of azobenzene units from trans to cis forms, the phase transitions take place in the same manner as in the thermotropic ones with a certain decrease of phase transition temperatures. It is also a new finding that at 202.5 °C at which 1 exhibits a Colr mesophase without photo-irradiation, the successive phase changes are induced by increasing the light intensity to the isotropic liquid (Iso) phase by way of a SmA phase. This means that the isothermal phase transitions among Iso, SmA and Colr phases can be controlled by light intensity. This is also the first example that the isothermal liquid crystalline phase transitions are controlled by photo-irradiation among three phases (Colr, SmA and Iso), which are also accompanied with the shape change of molecules between rod and disc.
Starting Page	25065
Ending Page	25071
Page Count	7
File Format	HTM / HTML PDF
ISSN	09599428
Volume Number	22
Issue Number	48
Journal	Journal of Materials Chemistry
DOI	10.1039/c2jm35518c
Language	English
Publisher	Royal Society of Chemistry
Access Restriction	Open
Subject Keyword	Triphenylene Thermotropic crystal Liquid crystal Anisotropy Wavelength Azobenzene Phase transition Mesophase Isotropy Isothermal process
Content Type	Text
Resource Type	Article
Subject	Chemistry Materials Chemistry

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Tuning oxygen permeability in azobenzene-containing side-chain liquid crystalline polymers

Photoinduced Phase Transitions in Rod-shaped Azobenzene with Different Alkyl Chain Length

Photoinduced isothermal phase transitions of liquid-crystalline macrocyclic azobenzenes.

Crystalline arrangement of some disc like compounds

Long Rod-Like Liquid Crystal Containing Azobenzene and the Applications in Phase-Transition Regulation and Orientation of Nematic Liquid Crystal

The mesophase in carbonaceous pitches

Lyotropic and thermotropic mesophase formation of novel tetra[oligo(ethyleneoxy)]-substituted phthalocyanines

Thermotropic liquid-crystalline properties of some novel hexuronic acid derivatives bearing a single or two alkyl chains

Triangular arylene ethynylene macrocycles: syntheses, optical, and thermotropic liquid crystalline properties

Thermal and photoinduced liquid crystalline phase transitions with a rod–disc alternative change in the molecular shape

Similar Documents

Tuning oxygen permeability in azobenzene-containing side-chain liquid crystalline polymers

Photoinduced Phase Transitions in Rod-shaped Azobenzene with Different Alkyl Chain Length

Photoinduced isothermal phase transitions of liquid-crystalline macrocyclic azobenzenes.

Crystalline arrangement of some disc like compounds

Long Rod-Like Liquid Crystal Containing Azobenzene and the Applications in Phase-Transition Regulation and Orientation of Nematic Liquid Crystal

The mesophase in carbonaceous pitches

Lyotropic and thermotropic mesophase formation of novel tetra[oligo(ethyleneoxy)]-substituted phthalocyanines

Thermotropic liquid-crystalline properties of some novel hexuronic acid derivatives bearing a single or two alkyl chains

Triangular arylene ethynylene macrocycles: syntheses, optical, and thermotropic liquid crystalline properties

Thermal and photoinduced liquid crystalline phase transitions with a rod–disc alternative change in the molecular shape