Induction of Antiferroelectric Phases in High Tilt Chiral Smectics by Doping with Bent-Shaped Liquid Crystals

Goc, F.; Selbmann, Ch.; Rauch, Sebastian; Heppke, G.; Dąbrowski, R.

doi:10.1080/15421400590954704

Cited by 12 publications

(5 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have taken into account that the compound that already has a TGB phase should contain less (R1) in the binary mixture. As in the case of binary mixture of two compounds, the miscibility study confirms the induction of a new mesophase and this new mesophase is not supposed to be present in either of the two compounds [9][10][11][12][13][14][15]. But we have found that the appearance of the smectic phase is different in the binary mixture from those of the individual compounds (R1 and R2).…”

Section: Resultssupporting

confidence: 58%

Stabilization of TGB Phase in the Binary Mixture of Rod-Shaped Compounds

Majumdar

Sinha

2010

Molecular Crystals and Liquid Crystals

View full text Add to dashboard Cite

A miscibility study of two cholesterol based rod-shaped compounds (R1 and R2) is presented. Both the compounds possess in common enantiotropic liquid crystalline phase sequence Cr ! SmA ! N Ã ! Isotropic, which is generally exhibited by cholesterol-based compounds. Additionally, one of the rod-shaped compounds (R1) possesses a twist-grain boundary (TGB) phase over a short temperature range. In the binary mixture of these two rod-shaped compounds the TGB phase was stabilized over a long temperature range compared to that in the individual molecule R1. In the binary mixture up to 20% (w=w) of compound R1 possessing the TGB phase exhibited enhancement of the temperature range of the TGB phase compared to that of individual compound R1. Further gradual increase of percentage of R1 in the binary mixture did not show any enhancement of the TGB phase compared to that of individual R1.

show abstract

Section: Resultssupporting

confidence: 58%

Stabilization of TGB Phase in the Binary Mixture of Rod-Shaped Compounds

Majumdar

Sinha

2010

Molecular Crystals and Liquid Crystals

View full text Add to dashboard Cite

show abstract

“…[114] On the other hand, results from a different approach using a small amount of bent-core molecules, which effectively act as an "anticlinicpromoting dopant" in a 458-tilt SmC* host, have recently appeared. [115] So far, problems with undesired high-temperature phases make the first mixtures difficult to use, but this approach may prove to be highly interesting in the future. With the discovery of AFLCs and the observation of the rich polymorphism of the AFLC compound MHPOBC (see Table 4) at the end of the 1980s, the full complexity of the chiral SmCtype structure became obvious.…”

Section: Aflc Materials Exhibiting High Director Tiltmentioning

confidence: 99%

Current Topics in Smectic Liquid Crystal Research

2006

View full text Add to dashboard Cite

Interest in the smectic liquid-crystalline state of matter received a substantial boost with the discovery by Meyer in the mid-1970s that a chiral smectic C (SmC*) phase exhibits a spontaneous electric polarization, and with the subsequent demonstration by Clark and Lagerwall of the surface-stabilized SmC* ferroelectric liquid crystal at the beginning of the 1980s. Since then, chiral smectic phases and their plethora of polar effects have dominated the research in this field, which today has reached a mature state where the first commercial microdisplay applications are now shipping in millions-per-year quantities. In this Review we discuss some of the topics of highest interest in current smectic liquid crystal research, and address application-relevant research (de Vries-type tilting transitions without defect generation and high-tilt antiferroelectric liquid crystals with perfect dark state) as well as more curiosity-driven research (the nature and origin of the chiral smectic C subphases and their intermediate frustrated states between ferro- and antiferroelectricity).

show abstract

“…Mixing compounds of different molecular structures has proven to be a useful tool to achieve lower transition temperatures in binary systems. Although bent-core compounds exhibit limited miscibility among themselves, a way to eschew this problem is to mix them with calamitic compounds [18][19][20][21][22][23][24], which could lead to unusual self-assemblies [25,26].…”

Section: Introductionmentioning

confidence: 99%

Mesophase behaviour of binary mixtures of bent-core and calamitic compounds

et al. 2013

View full text Add to dashboard Cite

The mesophase behaviour of binary mixtures of bent-core and calamitic liquid crystals is presented. The nematogenic 4,6-dichloro-1,3-phenylene bis[4'-(10-undecen-1-yloxy)-1,1'biphenyl-4-carboxylate] (I) was the banana-shaped component. As the calamitic compound ethyl 4'-(9-decen-1-yloxy)-1,1'-biphenyl-4-carboxylate (II), similar to one arm of the bentcore molecule, was used which exhibits smectic phases in a wide temperature range. A total of 6 mixtures with different compositions were prepared and studied by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction on non-oriented samples. In the mixtures a nematic phase is not concomitant with smectic A phase, and the temperature range of both phases highly depends on the concentration of the comprising compounds. Lowered melting temperatures have been observed for all mixtures with respect to that of the pure compounds. Unforeseen finding is the induction of a monotropic SmC phase in mixtures with lowest concentration of the bent-core compound. Semi-empirical quantum-chemical calculations have also been performed. Based on the calculated molecular conformation, as well as on collected X-ray diffraction data, a model for a possible selfassembly of the banana-shaped and calamitic compounds is proposed.

show abstract

Induction of Antiferroelectric Phases in High Tilt Chiral Smectics by Doping with Bent-Shaped Liquid Crystals

Cited by 12 publications

References 15 publications

Stabilization of TGB Phase in the Binary Mixture of Rod-Shaped Compounds

Stabilization of TGB Phase in the Binary Mixture of Rod-Shaped Compounds

Current Topics in Smectic Liquid Crystal Research

Mesophase behaviour of binary mixtures of bent-core and calamitic compounds

Contact Info

Product

Resources

About