Dielectric and orientational properties of nematogenic 4-n-octyl(4'-cyanophenyl)benzoate

• Autorzy: Bauman D. , Jadżyn J. , Wolarz E. , Modlińska A. , Dąbrowski R.
• Języki publikacji: EN

Abstrakty

EN

Experimental studies of the dielectric properties in the nematic and isotropic phases of 4-cyanophenyl-4'-n-octylbenzoate (8CPB) have been performed in the frequency range from 50 kHz to 100 MHz. The relaxation process related to the rotation around the short molecular axis has been analysed. The results obtained have revealed that in the vicinity of the I-N phase transition, the molecular subdiffusional rotation process occurs. It is connected with the pretransitional effects which are observed both in the static and dynamic dielectric measurements. On the basis of the temperature dependence of the relaxation time in the nematic and isotropic phases, the orientational order parameter < P2 > has been determined. The values of < P2 > obtained in this way have been compared with those evaluated from the measurements of the polarized electronic absorption of the dichroic dye, dissolved as guest probe in the mesogenic host.

Słowa kluczowe

EN

liquid crystal; dielectric properties; pretransitional effects; order parameter

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2010
• Tom: Vol. 18, No. 1
• Strony: 63--70
• Opis fizyczny: Bibliogr. 41 poz., wykr.

Twórcy

autor

Bauman D.

autor

Jadżyn J.

autor

Wolarz E.

autor

Modlińska A.

autor

Dąbrowski R.

• Faculty of Technical Physics, Poznań University of Technology, 13a Nieszawska Str., 60-965 Poznań, Poland,

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