Speaker
Aleksandra Deptuch
(Institute of Physics, Jagiellonian University, Kraków)
Description
Compounds from the homologous series of 4-n-pentylphenyl-4’-n-alkiloxybenzoates CnH2n+1-O-C6H6-COS-C6H6-C5H11, denoted as nOS5, known of creating liquid crystalline phases, are the subject of our recent studies. Some results for crystalline and liquid crystalline phases of 4-n-pentylphenyl-4’-n-heptyloxythiobenzoate (denoted as 7OS5), studied with differential scanning calorimetry (DSC), polarization microscopy (PM) and X-ray diffraction (XRD), will be presented.
DSC (DSC 8000 Perkin Elmer calorimeter, 6 K/min.) and PM (Nikon Eclipse LV100POL microscope, 6 K/min.) measurements deliver information about the phase sequences at heating and cooling as well. 7OS5 occurs in two liquid crystalline phases and polymorphism in a crystalline phase is also observed. In our DSC and PM measurements the following sequence of the phase transitions was observed: isotropic liquid → nematic → smectic C → crystal 1 while cooling and crystal 1 → crystal 2 → crystal 3 → nematic → isotropic liquid upon heating. In the simultaneous XRD-DSC measurements (SmartLab 9kW, Rigaku, CuKα, 2 K/min.) only one crystal phase during the first heating but two different crystal phases during the second heating were visible and no smectic order was detected while cooling. Single crystal X-ray analysis (SuperNova, Agilent Technologies, CuKα, 90 K) enabled us to solve the structure of 7OS5 in the crystalline phase. The compound crystallizes in an orthorhombic system (space group Pca21) with the cell parameters a= 54,285(5) Å, b= 5,5843(3) Å, c= 14,8411(10) Å.
Primary author
Aleksandra Deptuch
(Institute of Physics, Jagiellonian University, Kraków)
Co-authors
Prof.
Janusz Chruściel
(Institute of Chemistry, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland)
Joachim Kusz
(Institute of Physics, University of Silesia, Katowice, Poland)
Keigo Nagao
(Application Laboratories, Rigaku Corporation, Haijima, Japan)
Maria Książek
(Institute of Physics, University of Silesia, Katowice, Poland)
Mirosława D. Ossowska-Chruściel
(Institute of Chemistry, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland)
Monika Marzec
(Institute of Physics, Jagiellonian University, Kraków)
Takashi Matsumoto
(Application Laboratories, Rigaku Corporation, Haijima, Japan)
Teresa Jaworska-Gołąb
(Institute of Physics, Jagiellonian University, Kraków)
