Recent progresses in lyotropic chromonic liquid crystal research: elasticity, viscosity, defect structures, and living liquid crystals

Abstract

Lyotropic chromonic liquid crystals (LCLCs) are formed by linear stacks of disc-shaped molecular in water. Combined by weak, non-covalent forces, these aggregates are reversible, flexible and polydisperse. The self-assembly nature of the basic building units gives nematic LCLCs interesting physical properties, such as very small twist K 2 constant as compared with splay K 1 and bend K 3 constants, very large splay η splay and twist η twist viscosities, strong temperature dependence of K 1 , η splay , and η twist , diverse responses to different ionic additives, and large and azimuthally asymmetric disclination cores. We discuss our experimental studies on the viscoelastic properties and the fine structure of disclinations of LCLCs and attribute their unusual properties to the fact that LCLC aggregates are not fixed in size, but vary in response to changes of temperature, concentration and ionic content in the system. We further use these properties to explain intriguing phenomena in the 'living liquid crystals' composed of chromonic liquid crystal and motile bacteria Bacillus Subtilis.

Q-tensor model for undulatory swimming in lyotropic liquid crystal polymers

“…lyotropic chromonic LCs Zhou et al. 2014; Zhou 2018), LCPs can much more easily re-orient themselves when interacting with external fields (e.g. fluid flows, electric fields) to show large birefringence (Doi & Edwards 1988; Larson 1999).…”

Surface anchoring controls orientation of a microswimmer in nematic liquid crystal

“…nderstanding self-propulsion in complex and anisotropic fluids is a growing area of research [1][2][3][4][5][6][7][8] . A realization of the experimental system combining motile bacteria with a nematic liquid crystal (LC) was introduced in refs.…”

“…A realization of the experimental system combining motile bacteria with a nematic liquid crystal (LC) was introduced in refs. [2][3][4] . It was shown that bacteria in a LC demonstrate a wealth of intriguing phenomena, among which is the emergence of large-scale collective behavior.…”

Effect of the degree of protonation of amino acid dopants in Chirality amplification in DSCG Lyotropic Nematic phases.

“…The DSCG-LCLC system has been utilized in many applications. 7,8,9 Notable among these are as an NMR aligning medium for the study of cyclodextrin host-guest complexes through residual quadrupolar splittings 10 and for structural studies of small molecules through the measurement of residual dipolar couplings (RDCs). 11,12,13,14 In addition, the nematic phase of DSCG has proven to be sensitive to the presence of small molecules (dopants).…”