Molecular engineering of triphenylene-based discotic liquid crystal conductors

• Autorzy: Bushby R. J. , Donovan K. J. , Kreouzis T. , Lozman O. R.
• Języki publikacji: EN

Abstrakty

EN

2,3,6,7,10,11-hexakis(hexyloxy)triphenylene (HAT6) gives a columnar hexagonal mesophase between 70 and 100°C and a hole mobility of 7.1x10⁻⁴ cm²V⁻¹s⁻¹. Two methods are compared for extending the mesophase range to encompass the operationally-significant room temperature range and for enhancing the charge-carrier mobility: introduction of a lateral nuclear dipole and formation of a CPI (complementary polytopic interaction) "compound". Introduction of two fluorine substituents into the nucleus of HAT6 gives 1,4-difluoro-2,3,6,7,10,11-hexakis(hexyloxy)triphenylene (2F-HAT6). This has a lateral nuclear dipole and gives a columnar hexagonal mesophase from below room temperature to 121°C whereas the CPI mixture of 2F-HAT6 with 2,3,6,7,10,11-hexakis(4-nonylphenyl)triphenylene (PTP9) has a columnar mesophase from below room temperature to 129°C. At 100°C the time-of-flight hole mobilities of these two systems are increased to 1.6Y10n3 cm²V⁻¹s⁻¹ for 2F-HAT6 and 1.5Y10⁻² cm²V⁻¹s⁻¹ for the CPI compound 2F-HAT6 + PTP9.

Słowa kluczowe

EN

liquid crystal; semiconductor; time-of-flight; photoconduction; hole mobility; molecular engineering

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2005
• Tom: Vol. 13, No. 4
• Strony: 269--279
• Opis fizyczny: Bibliogr. 37 poz., wykr.

Twórcy

autor

Bushby R. J.

• Centre for Self Organising Molecular Systems (SOMS), University of Leeds, Woodhouse Lane, LS2 9JT Leeds, United Kingdom

autor

Donovan K. J.

• Queen Mary and Westfield College, University of London, Mile End Road, E1-4NS London, United Kingdom

autor

Kreouzis T.

• Queen Mary and Westfield College, University of London, Mile End Road, E1-4NS London, United Kingdom

autor

Lozman O. R.

• Centre for Self Organising Molecular Systems (SOMS), University of Leeds, Woodhouse Lane, LS2 9JT Leeds, United Kingdom

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