Electro-optical Kerr effect of nematic mixtures comprised of 6CHBT and 6BOBT

• Autorzy: Tajalli H. , Ghanadzadeh A. , Khoshsima H. , Zhalefar P.
• Konferencja: Conference on Liquid Crystals : Chemistry, Physics and Applications ; (17 ; 09.2007 ; Augustów, Poland)
• Języki publikacji: EN

Abstrakty

EN

Static Kerr effect and the pre-transition temperature were investigated for the 6CHBT, 6BOBT and the nematic mixtures, M₁ (40% 6CHBT: 60% 6BOBT), M₂ (30% 6CHBT: 70% 6BOBT) and M₃ (20% 6CHBT: 80% 6BOBT) at temperatures above the nematic-isotropic transition temperature. The linear dependence of (T-T*)⁻¹ on the Kerr constant is found to be in good agreement with the predications of the Landau-De Gennes model. The hypothetical second order phase transition temperatures and susceptibility values were determined for these compounds.

Słowa kluczowe

EN

liquid crystals; nematic mixture; electro-optic Kerr effect; electric birefringence; pre-transition behaviour

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2008
• Tom: Vol. 16, No. 4
• Strony: 386--389
• Opis fizyczny: Bibliogr. 15 poz., wykr.

Twórcy

autor

Tajalli H.

autor

Ghanadzadeh A.

autor

Khoshsima H.

autor

Zhalefar P.

• Center of Applied Physics and Astronomy, Tabriz University, Tabriz, Iran

Bibliografia

• 1. J. Kerr, “A new relation between electricity and light”, Phil. Mag. 50, 337-348 (1875).
• 2. H.J. Coles, “Laser and electric field induced birefringence studies on the cyanobiphenyl homologues”, Mol. Cryst. Liq. Cryst. 49, 67-74 (1978).
• 3. A. Sinha, T.A. Prasada Rao, V.R.K. Murthy, and R. Dabrowski, “Kerr effect investigations in a liquid crystal”, Liq. Cryst. 27, 191-194 (2000).
• 4. A. Ghanadzadeh and M.S. Beevers, “The static Kerr effect of two nematic mixtures comprised of pentyl and heptyl cyanobiphenyls in the isotropic phase”, J. Mol. Liq. 112, 141-145 (2004).
• 5. J. Philip and T.A. Prasada Rao, “Transient Kerr response in a nematic liquid crystal”, J. Phys. D: Appl. Phys. 25, 1231-1234 (1992).
• 6. J. Philip and T.A. Prasada Rao, “Transient Kerr effect in nematic liquid crystal mixtures”, J. Mol. Liq. 50, 215-223 (1991).
• 7. H.J. Coles and B.R. Jennings, “Static and optical Kerr effect in the nematogen MBBA”, Mol. Phys. 31, 571-580 (1976).
• 8. B. Pouligny, J.P. Marcerou, J.R. Lalanne, and H.J. Coles, “Pretransitional effects in the isotropic phases of some alkyl cyanobiphenyls”, Mol. Phys. 49, 583-598 (1983).
• 9. J. Philip and T.A. Prasada Rao, “Kerr-effect investigations in a nematic liquid crystal”, Phys. Rev. A46, 2163-2165 (1992).
• 10. B. Malraison, Y. Poggi, and J.C. Filippini, “Breakdown of the Landau theory in the vicinity of the nematic-isotropic transition”, Solid State Commun. 31, 843-845 (1979).
• 11. C.C. Wang,” Nonlinear susceptibility constants and selffocusing of optical beams in liquids”, Phys. Rev. 152, 149-156 (1966).
• 12. P.G. de Gennes, “Short range order in the isotropic phase of nematic”, Mol. Cryst. Liq. Cryst. 12, 193-201 (1971). 13. M.S. Beevers and G. Khanarian, “Measurement of Kerr constants of conducting liquids”, Aus. J. Chem. 3, 263-269 (1979).
• 14. C.T. O’Konski and A.J. Haltner, “Characterization of the monomer and dimer of tobacco mosaic virus by transient electric birefringence”, J. Am. Chem. Soc. 78, 3604-3610 (1956).
• 15. W. Maier and A. Saupe, “Eine einfache molekular-statistische Theorie des nematischen kristallinflüssigen Phase”, Z. Naturforsch. 14A, 882-889 (1959).