Orientational order in nematic, smectic A, and smectic C phases of {VERTICAL-ALIGN: text-bottom' alt=GPHT_A_233872_O_XML_IMAGES\GPHT_A_233872_O_ILM0001.gif} < src=' > {/ampp/image?path=/713647403/779214505/gpht_a_233872_o_ilm0001.gif} doped with dichroic dye {section}

• Published in: Phase transitions Vol. 80; no. 6-7; pp. 599 - 613
• Main Authors: Bauman, D, Mykowska, E, Chrzumnicka, E, Czechowski, G, Jadzdotyn, J
• Format: Journal Article
• Language: English
• Published: 01.06.2007
• ISSN: 0141-1594
• DOI: 10.1080/01411590701339781

The long-range orientational order of mesogenic 4-n-pentylphenylthio-4'-n-octyloxybenzoate ({VERTICAL-ALIGN: text-bottom' alt=GPHT_A_233872_O_XML_IMAGES\GPHT_A_233872_O_ILM0002.gif} < src=' > {/ampp/image?path=/713647403/779214505/gpht_a_233872_o_ilm0002.gif}) doped with a dichroic dye was studied by means of electronic absorption and fluorescence measurements. The order parameters P2 > and P4 > as well as the orientational distribution function were determined on the basis of absorption and emission spectra of linearly polarized light recorded as a function of temperature in the nematic, smectic A and smectic C phases. An influence of the dye molecular structure on the orientational order of the dye/liquid crystal mixture was observed. A correlation between the order parameter values and the phase transitions temperature shift due to the dye addition was found.