Jul 6 – 10, 2015
Institute of Nuclear Physics PAN, Kraków
Europe/Warsaw timezone

Intra- and intermolecular dynamics in liquid-crystalline substance with ferro- and antiferroelectric phases

Jul 7, 2015, 6:30 PM
1h
Olimpia Conference Room (Crown Piast Hotel)

Olimpia Conference Room

Crown Piast Hotel

Board: 28

Speaker

Dr Łukasz Kolek (Department of Materials Sciences, Rzeszów University of Technology, Poland)

Description

For 1-[3-fluoro-4-(1-methylheptyloxycarbonyl)phenyl]-2-[4’-2,2,3,3,4,4,4-heptafluoro butoxybutoxy)biphenyl -4-yl]ethane (1F7) built of chiral molecules, intra- and intermolecular dynamics is presented. Intermolecular dynamics was studied by dielectric spectroscopy while intramolecular dynamics by nuclear magnetic resonance and infrared spectroscopy. In ferroelectric SmC*, antiferroelectric SmC*A and highly ordered SmI*A phases of 1F7 the relaxation processes were detected in frequency range from 0.05 Hz to 3 MHz. Mechanisms of intermolecular dynamics were identified with the help of the bias field [1]. Using NMR technics the following intramolecular motions were detected: rotation of the CH3 and CF3 groups and reorientation of the phenyl rings. In liquid-crystalline phases molecular processes connected with rotation molecule around short and long axis were confirmed. Relaxation time T1, correlation time τ and activation barriers were calculated for individual motions. Infrared spectroscopy method shows rich dynamics in Cr1 and Cr2 crystalline phases [2]. References [1] Kolek, Ł.; Massalska-Arodź, M.; Paluch, M.; Adrjanowicz, K.; Rozwadowski, T.; Majda, D.; Liq. Cryst. 2013, 40, 1082. [2] Kolek, Ł.; Massalska-Arodź, M.; Hołderna-Natkaniec, K.; Woźniak-Braszak, A.; Juszyńska-Gałązka, E.; Intramolecular dynamics of a liquid crystal with fluorinated molecules (1F7) (in preparation).

Primary author

Dr Łukasz Kolek (Department of Materials Sciences, Rzeszów University of Technology, Poland)

Co-authors

Dr Aneta Woźniak-Braszak (Institute of Physics, Adam Mickiewicz University, Poznań) Dr Ewa Juszyńska-Gałązka (Institute of Nuclear Physics PAN, Kraków) Prof. Krystyna Hołderna-Natkaniec (Institute of Physics, Adam Mickiewicz University, Poznań) Prof. Maria Massalska-Arodź (Institute of Nuclear Physics PAN, Kraków) Dr Tomasz Rozwadowski (Institute of Nuclear Physics PAN, Kraków)

Presentation materials