[PDF]    http://dx.doi.org/10.3952/physics.v55i1.3055

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 55, 2434 (2015)


THERMOTROPIC, REFRACTING AND THERMO-OPTICAL PROPERTIES IN THREE HOMOLOGS Of 4-N-ALKYL-4'-CYANOBIPHENYLS
Arif Nesrullajev
Department of Physics, Faculty of Science, Mugla Sitki Koçman University, 48000 Kötekli Muğla, Turkey
E-mail: arifnesr@mu.edu.tr

Received 1 October 2014; revised 25 November 2014; accepted 10 December 2014

Investigations of temperature behaviour of the mean refractive index n, ordinary no and extraordinary ne refractive indices, and birefringence Δn have been carried out for three homologues of 4-n-alkyl-4'-cyanobiphenyls (n = 8, 10, 12). The principal polarizabilities α0 and αe, effective geometry parameter αeg and average polarizability αave have been calculated using the isotropic internal field model (Vuks approach). Temperature behaviour of the order parameter in regions of the smectic A–nematic, nematic–isotropic liquid and smectic A–isotropic liquid is discussed. All of the optical and orientational parameters, which have been obtained in this work, are in good agreement with the theoretical approach.
Keywords: liquid crystals, refractive properties, optical birefringence, phase transitions
PACS: 42.25.Lc; 42.70.Df; 64.70.M

TRIJŲ 4-N-ALKIL-4'-CIANOBIFENILŲ TERMOTROPINĖS, ATSPINDŽIO IR TERMOOPTINĖS SAVYBĖS

Arif Nesrullajev
Mugla Sitki Koçman universiteto Mokslo fakulteto Fizikos katedra, Kötekli Muğla, Turkija

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