20.500.12556/RUL-152840 Optical switching of bent-core liquid crystals with azocinnamoyl units We report on observations of optical switching in bent-core liquid crystals possessing azocinnamoyl groups in both elongated side arms. UV-activated switching was observed in two of the synthesised materials, both of which were studied optically and with dielectric spectroscopy. Polarising microscopy was used to measure the changes in optical transmittance, and while no illumination effect was seen in the nematic phase, visible changes were observed in the smectic phase, most pronounced in the close vicinity of the smectic to nematic-phase transition. Switching dynamics was characterised, and we found that the average switching time varies strongly with temperature. The relaxation process is faster (below 200 ms) and exhibits no significant temperature dependence. Dielectric measurements have shown that the observed smectic C phases were not polar with the molecules possessing a rather small electric dipole moment. Upon illumination, small differences in the dielectric permittivity were observed only in the smectic phase, suggesting that the illumination effect can be attributed to changes in the molecular conformational and orientational order. bent-core liquid crystals photo-switching azocinnamoyl group optical switching switching dynamics tekoči kristali z upognjeno sredico fotopreklapljanje azocinamat optično preklapljanje dinamika preklapljanja tekoči kristali true false true Angleški jezik Slovenski jezik Članek v reviji 2023-12-08 14:04:35 2023-12-08 14:04:37 2023-12-09 03:49:42 0000-00-00 00:00:00 2023 0 0 Str. 1599–1607 no. 7/10 Vol. 50 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 532 1366-5855 10.1080/02678292.2023.2179120 142935299 Optical_switching_of_bent-core_liquid_crystals_with_azocinnamoyl_units.pdf Optical_switching_of_bent-core_liquid_crystals_with_azocinnamoyl_units.pdf 1 48B7EEFB9C8A6A2A9363752830A7847B b22339b7409f3ded9fd7d91e8e09abad9b79f137d7be7450c05d556e65f222e9 a9cf94a9-95ca-11ee-9c20-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=178528 https://www.tandfonline.com/doi/full/10.1080/02678292.2023.2179120 1 57be9395-95ca-11ee-9c20-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=178526 Fakulteta za matematiko in fiziko 0 0 0