Effect of lateral fluorination in antiferroelectric and ferroelectric mesophases: synchrotron X-ray diffraction, dielectric spectroscopy and electro-optic study

Dey, K.; Mandal, Pradip; Dąbrowski, R.

doi:10.1016/j.jpcs.2015.08.016

Cited by 12 publications

(3 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As can be seen, a polarization hump appears on the time scale away from the edge of the applied voltage. The time interval between the edge of the applied voltage and the maxima of the polarization hump gives the switching time of the LC material . Under the low voltage, the polarization reversal current peak was relatively broad and it becomes sharper with increasing voltage.…”

Section: Resultsmentioning

confidence: 99%

“…The time interval between the edge of the applied voltage and the maxima of the polarization hump gives the switching time of the LC material. 36 Under the low voltage, the polarization reversal current peak was relatively broad and it becomes sharper with increasing voltage. As shown in Figure 10b, the switching time decreases with increasing voltage because higher voltage forces molecules to switch faster.…”

Section: ■ Experimental Sectionmentioning

confidence: 97%

See 1 more Smart Citation

Ferroelectric Nematic and Ferrielectric Smectic Mesophases in an Achiral Bent-Core Azo Compound

Kumar

Prasad

2018

J. Phys. Chem. B

View full text Add to dashboard Cite

Here, we report the observation of ferroelectric nematic and ferrielectric smectic mesophases in an achiral bent-core azo compound consisting of nonsymmetrical molecules with a lateral fluoro substitution on one of the wings. These mesophases are enantiotropic in nature with fairly low transition temperatures and wide mesophase ranges. The liquid crystalline properties of this compound are investigated using polarizing optical microscope, differential scanning calorimeter, X-ray diffraction, and electro-optical studies. As revealed by X-ray diffraction measurements, the nematic mesophase is composed of skewed cybotactic clusters and, in the smectic mesophase, the molecules are tilted with respect to the layer normal. The polar order in these mesophases was confirmed by the electro-optical switching and dielectric spectroscopy measurements. The dielectric study in the nematic mesophase shows a single relaxation process at low frequency ( f < 1 kHz) measured in the range 10 Hz to 5 MHz, which is attributed to the collective motion of the molecules within cybotactic clusters. The formation of local polar order in these clusters leads to a ferroelectric-like polar switching in the nematic mesophase. Of particular interest is the fact that the smectic phase exhibits a field induced ferrielectric state, which can be exploited for designing of the potential optical devices due to multistate switching.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: ■ Experimental Sectionmentioning

confidence: 97%

Ferroelectric Nematic and Ferrielectric Smectic Mesophases in an Achiral Bent-Core Azo Compound

Kumar

Prasad

2018

J. Phys. Chem. B

View full text Add to dashboard Cite

show abstract

“…Â 100%: Response time was determined by measuring the time delay of occurrence of polarization bump from the applied square pulse edge (4-25 Vpp, 10 Hz) while monitoring, in a storage oscilloscope (Tektronix TDS 2012B), the voltage across a resistor in series with the cell. 23,24…”

Section: Methodsmentioning

confidence: 99%

Wide range room temperature electroclinic liquid crystal mixture with large induced tilt and very small layer contraction

Debnath

Sinha

Mandal

2016

Journal of Applied Physics

View full text Add to dashboard Cite

Optical polarizing microscopy, synchrotron X-ray scattering, and electro-optic studies in the SmA* phase of a formulated wide range room temperature liquid crystal mixture indicate a large electric field induced optical tilt up to 23.5 along with a very small contraction of smectic layers. Applied field primarily lifts the zero-field degeneracy of the azimuthal order of the molecules in smectic layers resulting in small layer contraction. V

show abstract

Influence of Bias on Dielectric Properties of Mesophases of a Laterally Fluorinated Antiferroelectric Liquid Crystal

Dey¹,

Mandal

Dąbrowski

2017

Springer Proceedings in Physics

View full text Add to dashboard Cite

Effect of lateral fluorination in antiferroelectric and ferroelectric mesophases: synchrotron X-ray diffraction, dielectric spectroscopy and electro-optic study

Cited by 12 publications

References 38 publications

Ferroelectric Nematic and Ferrielectric Smectic Mesophases in an Achiral Bent-Core Azo Compound

Ferroelectric Nematic and Ferrielectric Smectic Mesophases in an Achiral Bent-Core Azo Compound

Wide range room temperature electroclinic liquid crystal mixture with large induced tilt and very small layer contraction

Influence of Bias on Dielectric Properties of Mesophases of a Laterally Fluorinated Antiferroelectric Liquid Crystal

Contact Info

Product

Resources

About