Search for nematic biaxiality in bent-core mesogens: an X-ray diffraction perspective

References

• Freiser MJ. Ordered states of a nematic liquid. Phys Rev Lett. 1970;24:1041–1043. doi:10.1103/PhysRevLett.24.1041.
   Web of Science ®Google Scholar
• Luckhurst GR, Sluckin TJ, editors. Biaxial nematic liquid crystals: theory, simulation, and experiment. Chichester: Wiley; 2015.
   Google Scholar
• Berardi R, Muccioli L, Zannoni C. Field response and switching times in biaxial nematics. J Chem Phys. 2008;128:024905. doi:10.1063/1.2815804.
   PubMed Web of Science ®Google Scholar
• Luckhurst GR. Biaxial nematic liquid crystals: fact or fiction? Thin Solid Films. 2001;393:40–52. doi:10.1016/S0040-6090(01)01091-4.
   Web of Science ®Google Scholar
• Tschierske C, Photinos DJ. Biaxial nematic phases. J Mater Chem. 2010;20:4263–4294. doi:10.1039/b924810b.
   Web of Science ®Google Scholar
• Archarya BR, Primak A, Kumar S, et al. The elusive thermotropic biaxial nematic phase in rigid bent-core molecules. Pramana–J Phys. 2003;61:231–237. doi:10.1007/BF02708305.
   Web of Science ®Google Scholar
• Acharya BR, Primak A, Kumar S. Biaxial nematic phase in bent-core thermotropic mesogens. Phys Rev Lett. 2004;92:145506. doi:10.1103/PhysRevLett.92.145506.
   PubMed Web of Science ®Google Scholar
• Madsen LA, Dingemans TJ, Nakata M, et al. Thermotropic biaxial nematic liquid crystals. Phys Rev Lett. 2004;92:145505. doi:10.1103/PhysRevLett.92.145505.
   PubMed Web of Science ®Google Scholar
• Luckhurst GR. Liquid crystals: a missing phase found at last? Nature. 2004;430:413–414. doi:10.1038/430413a.
   PubMed Web of Science ®Google Scholar
• Jákli A. Liquid crystals of the twenty-first century–nematic phase of bent-core molecules. Liq Cryst Rev. 2013;1:65–82. doi:10.1080/21680396.2013.803701.
   Web of Science ®Google Scholar
• Gleeson HF, Kaur S, Görtz V, et al. The nematic phases of bent-core liquid crystals. Chem Phys Chem. 2014;15:1251–1260. doi:10.1002/cphc.201400014.
   Web of Science ®Google Scholar
• Kumar S, Gowda AN. The chemistry of bent-core molecules forming nematic liquid crystals. Liq Cryst Rev. 2015;3:99–145. doi:10.1080/21680396.2015.1061958.
   Web of Science ®Google Scholar
• Samulski ET. Meta-cybotaxis and nematic biaxiality. Liq Cryst. 2010;37:669–678. doi:10.1080/02678292.2010.488938.
   Web of Science ®Google Scholar
• Francescangeli O, Vita F, Samulski ET. The cybotactic nematic phase of bent-core mesogens: state of the art and future developments. Soft Matter. 2014;10:7685–7691. doi:10.1039/C4SM01256A.
   PubMed Web of Science ®Google Scholar
• Vanakaras AG, Photinos DJ. Thermotropic biaxial nematic liquid crystals: spontaneous or field stabilized? J Chem Phys. 2008;128:154512. doi:10.1063/1.2897993.
   PubMed Web of Science ®Google Scholar
• Peroukidis SD, Karahaliou PK, Vanakaras AG, et al. Biaxial nematics: symmetries, order domains and field-induced phase transitions. Liq Cryst. 2009;36:727–737. doi:10.1080/02678290902814700.
   Web of Science ®Google Scholar
• Cooper LL, Samulski ET, Scharrer E. Towards room temperature biaxial nematics. Mol Cryst Liq Cryst. 2009;511:1673–1687. doi:10.1080/15421400903053826.
   Web of Science ®Google Scholar
• Speetjens F, Lindborg J, Tauscher T, et al. Low nematic onset temperatures and room temperature cybotactic behavior in 1,3,4-oxadiazole-based bent-core mesogens possessing lateral methyl groups. J Mater Chem. 2012;22:22558–22564. doi:10.1039/c2jm33705c.
   Web of Science ®Google Scholar
• Nguyen J, Wonderly W, Tauscher T, et al. The effects of lateral halogen substituents on the low-temperature cybotactic nematic phase in oxadiazole based bent-core liquid crystals. Liq Cryst. 2015;42:1754–1764. doi:10.1080/02678292.2015.1085599.
   Web of Science ®Google Scholar
• Glebowska A, Vita F, Francescangeli O, et al. Molecular engineering room-temperature bent-core nematics. Liq Cryst. 2015;42:829–839.
   Web of Science ®Google Scholar
• Prasad V, Kang S-W, Suresh KA, et al. Thermotropic uniaxial and biaxial nematic and smectic phases in bent-core mesogens. J Am Chem Soc. 2005;127:17224–17227. doi:10.1021/ja052769n.
   PubMed Web of Science ®Google Scholar
• Acharya BR, Kang SW, Kumar S. X-ray diffraction from the uniaxial and biaxial nematic phases of bent-core mesogens. Liq Cryst. 2008;35:109–118. doi:10.1080/02678290701817326.
   Web of Science ®Google Scholar
• Acharya BR, Kang SW, Prasad V, et al. Role of molecular structure on X-ray diffraction in uniaxial and biaxial phases of thermotropic liquid crystals. J Phys Chem B. 2009;113:3845–3852. doi:10.1021/jp810333r.
   PubMed Web of Science ®Google Scholar
• Acharya BR, Kumar S. Fact or fiction: cybotactic groups in the nematic phase of bent core mesogens. In: Li Q, editor. Liquid crystals beyond displays: chemistry, physics, and applications. Hoboken: Wiley; 2012. p. 427–448.
   Google Scholar
• Southern CD, Brimicombe PD, Siemianowski SD, et al. Thermotropic biaxial nematic order parameters and phase transitions deduced by Raman scattering. EPL. 2008;82:56001. doi:10.1209/0295-5075/82/56001.
   Web of Science ®Google Scholar
• Francescangeli O, Stanic V, Torgova SI, et al. Ferroelectric response and induced biaxiality in the nematic phase of bent-core mesogens. Adv Funct Mater. 2009;19:2592–2600. doi:10.1002/adfm.v19:16.
   Web of Science ®Google Scholar
• Vaupotič N, Szydlowska J, Salamonczyk M, et al. Structure studies of the nematic phase formed by bent-core molecules. Phys Rev E. 2009;80:030701. doi:10.1103/PhysRevE.80.030701.
   Web of Science ®Google Scholar
• Francescangeli O, Samulski ET. Insights into the cybotactic nematic phase of bent-core molecules. Soft Matter. 2010;6:2413–2420. doi:10.1039/c003310c.
   Web of Science ®Google Scholar
• Keith C, Lehmann A, Baumeister U, et al. Nematic phases of bent-core mesogens. Soft Matter. 2010;6:1704–1721. doi:10.1039/b923262a.
   Web of Science ®Google Scholar
• Hong SH, Verduzco R, Williams JC, et al. Short-range smectic order in bent-core nematic liquid crystals. Soft Matter. 2010;6:4819–4827. doi:10.1039/c000362j.
   Web of Science ®Google Scholar
• Francescangeli O, Vita F, Ferrero C, et al. Cybotaxis dominates the nematic phase of bent-core mesogens: a small-angle diffuse X-ray diffraction study. Soft Matter. 2011;7:895–901. doi:10.1039/C0SM00745E.
   Web of Science ®Google Scholar
• Chakraborty S, Gleeson JT, Jákli A, et al. A comparison of short-range molecular order in bent-core and rod-like nematic liquid crystals. Soft Matter. 2013;9:1817–1824. doi:10.1039/C2SM27177J.
   Web of Science ®Google Scholar
• Hong SH, Verduzco R, Gleeson JT, et al. Nanostructures of liquid crystal phases in mixtures of bent-core and rod-shaped molecules. Phys Rev E. 2011;83:061702. doi:10.1103/PhysRevE.83.061702.
   Web of Science ®Google Scholar
• Shanker G, Prehm M, Tschierske C. Liquid-crystalline heterodimesogens and ABA-heterotrimesogens comprising a bent 3,5-diphenyl-1,2,4-oxadiazole central unit. Beilstein J Org Chem. 2012;8:472–485. doi:10.3762/bjoc.8.54.
   PubMed Web of Science ®Google Scholar
• Weissflog W, Baumeister U, Tamba M-G, et al. Unexpected liquid crystalline behaviour of three-ring bent-core mesogens: bis(4-subst.-phenyl) 2-methyl-iso-phthalates. Soft Matter. 2012;8:2671–2685. doi:10.1039/c2sm07064b.
   Web of Science ®Google Scholar
• Francescangeli O, Vita F, Fauth F, et al. Extraordinary magnetic field effect in bent-core liquid crystals. Phys Rev Lett. 2011;107:207801. doi:10.1103/PhysRevLett.107.207801.
   PubMed Web of Science ®Google Scholar
• Vita F, Placentino IF, Ferrero C, et al. Electric field effect on the phase diagram of a bent-core liquid crystal. Soft Matter. 2013;9:6475–6481. doi:10.1039/c3sm50852h.
   Web of Science ®Google Scholar
• Dingemans TJ, Madsen LA, Francescangeli O, et al. The biaxial nematic phase of oxadiazole biphenol mesogens. Liq Cryst. 2013;41:1655–1677. doi:10.1080/02678292.2013.824119.
   Web of Science ®Google Scholar
• Nagaraj M, Lehmann A, Prehm M, et al. Evidence of a polar cybotactic smectic A phase in a new fluorine substituted bent-core compound. J Mater Chem. 2011;21:17098–17103. doi:10.1039/c1jm13140k.
   Web of Science ®Google Scholar
• Shanker G, Nagaraj M, Kocot A, et al. Nematic phases in 1,2,4-oxadiazole-based bent-core liquid crystals: Is there a ferroelectric switching? Adv Funct Mater. 2012;22:1671–1683. doi:10.1002/adfm.v22.8.
   Web of Science ®Google Scholar
• Shanker G, Prehm M, Nagaraj M, et al. 1,2,4-oxadiazole-based bent-core liquid crystals with cybotactic nematic phases. ChemPhysChem. 2014;15:1323–1335. doi:10.1002/cphc.201301070.
   PubMed Web of Science ®Google Scholar
• Vita F, Sparnacci K, Panzarasa G, et al. Evidence of cybotactic order in the nematic phase of a main-chain liquid crystal polymer with bent-core repeat unit. ACS Macro Lett. 2014;3:91–95. doi:10.1021/mz400518x.
   PubMed Web of Science ®Google Scholar
• Vita F, Tauscher T, Speetjens F, et al. Evidence of biaxial order in the cybotactic nematic phase of bent-core mesogens. Chem Mat. 2014;26:4671–4674. doi:10.1021/cm5019822.
   Web of Science ®Google Scholar
• Vita F, Tauscher T, Speetjens F, et al. Insights into biaxial ordering of bent-core nematics: X-ray diffraction evidence. Mol Cryst Liq Cryst. 2015;611:171–179. doi:10.1080/15421406.2015.1030232.
   Web of Science ®Google Scholar
• Kim Y-K, Cukrov G, Vita F, et al. Search for microscopic and macroscopic biaxiality in the cybotactic nematic phase of new oxadiazole bent-core mesogens. Phys Rev E. Forthcoming 2016;93:062701. doi:10.1103/PhysRevE.93.062701.
   Web of Science ®Google Scholar
• Berardi R, Muccioli L, Orlandi S, et al. Computer simulations of biaxial nematics. J Phys: Condens Matter. 2008;20:463101.
   PubMed Web of Science ®Google Scholar
• Galerne Y. Characterization of biaxial nematic phases in the thermotropic liquid crystals. Mol Cryst Liq Cryst. 1998;323:211–229. doi:10.1080/10587259808048443.
   Web of Science ®Google Scholar
• Bruce DW. Towards the biaxial nematic phase through molecular design. Chem Rec. 2004;4:10–22. doi:10.1002/tcr.10073.
   PubMed Web of Science ®Google Scholar
• Lehmann M. Biaxial nematics from their prediction to the materials and the vicious circle of molecular design. Liq Cryst. 2011;38:1389–1405. doi:10.1080/02678292.2011.624374.
   Web of Science ®Google Scholar
• Emsley JW. Nuclear magnetic resonance of liquid crystals. Dordrecht: Reidel; 1983.
   Google Scholar
• Dunmur DA, Palffy-Muhoray P. Effect of electric and magnetic fields on orientational disorder in liquid crystals. J Phys Chem. 1988;92:1406–1419. doi:10.1021/j100317a010.
   Web of Science ®Google Scholar
• Yu LJ, Saupe A. Observation of a biaxial nematic phase in potassium laurate–1-decanol–water mixtures. Phys Rev Lett. 1980;45:1000–1003. doi:10.1103/PhysRevLett.45.1000.
   Web of Science ®Google Scholar
• Viney C, Mitchell GR, Windle AH. Biaxial optical properties of thermotropic random copolyesters. Mol Cryst Liq Cryst. 1985;129:75–108. doi:10.1080/15421408408084167.
   Web of Science ®Google Scholar
• Ebert M, Herrmann-Schönherr O, Wendorff JH, et al. Evidence for a biaxial nematic phase in sanidic aromatic polyamides with 1,4,7-trioxaoctyl side-chains. Macromol Chem Rapid Commun. 1988;9:445–451. doi:10.1002/marc.1988.030090612.
   Google Scholar
• Brömmel F, Zou P, Finkelmann H, et al. Influence of the mesogenic shape on the molecular dynamics and phase-biaxiality of liquid crystal main-chain polymers. Soft Matter. 2013;9:1674–1677. doi:10.1039/C2SM27293H.
   Web of Science ®Google Scholar
• Brömmel F, Stille W, Finkelmann H, et al. Molecular dynamics and biaxiality of nematic polymers and elastomers. Soft Matter. 2011;7:2387–2401. doi:10.1039/c0sm01116a.
   Web of Science ®Google Scholar
• Hessel F, Herr RP, Finkelmann H. Synthesis and characterization of biaxial nematic side-chain polymers with laterally attached mesogenic groups. Macromol Chem. 1987;188:1597–1611. doi:10.1002/macp.1987.021880706.
   Web of Science ®Google Scholar
• Severing K, Saalwachter K. Biaxial nematic phase in a thermotropic liquid-crystalline side-chain polymer. Phys Rev Lett. 2004;92:125501. doi:10.1103/PhysRevLett.92.125501.
   PubMed Web of Science ®Google Scholar
• Severing K, Stibal-Fischer E, Hasenhindl A, et al. Phase biaxiality in nematic liquid crystalline side-chain polymers of various chemical constitutions. J Phys Chem B. 2006;110:15680–15688. doi:10.1021/jp0605348.
   PubMed Web of Science ®Google Scholar
• Malthête J, Tinh NH, Levelut A-M. New mesogens with six, four or three paraffinic chains. J Chem Soc Chem Commun. 1986;1548−1549. doi:10.1039/C39860001548.
   Google Scholar
• Chandrasekhar S, Sadashiva BK, Ratna BR, et al. A biaxial nematic liquid crystal. Pramana. 1988;30:L491−L494. doi:10.1007/BF02935608.
   Web of Science ®Google Scholar
• Chandrasekhar S. Biaxial nematic liquid crystals in low molecular weight thermotropic systems. Mol Cryst Liq Cryst. 1994;243:1−9. doi:10.1080/10587259408037758.
   Web of Science ®Google Scholar
• Praefcke K, Kohne B, Gundogan B, et al. News on nematic-biaxial liquid crystals. Mol Cryst Liq Cryst. 1991;198:393–405. doi:10.1080/00268949108033415.
   Web of Science ®Google Scholar
• Senyuk B, Wonderly H, Mathews M, et al. Surface alignment, anchoring transitions, optical properties, and topological defects in the nematic phase of thermotropic bent-core liquid crystal A131. Phys Rev E. 2010;82:041711. doi:10.1103/PhysRevE.82.041711.
   Web of Science ®Google Scholar
• Kim Y-K, Breckon R, Chakraborty S, et al. Properties of the broad-range nematic phase of a laterally linked H-shaped liquid crystal dimer. Liq Cryst. 2014;41:1345–1355. doi:10.1080/02678292.2014.920930.
   Web of Science ®Google Scholar
• Kim Y-K, Cukrov G, Xiang J, et al. Domain walls and anchoring transitions mimicking nematic biaxiality in the oxadiazole bent-core liquid crystal C7. Soft Matter. 2015;11:3963−3970. doi:10.1039/C5SM00580A.
   PubMed Web of Science ®Google Scholar
• Guinier A. X-ray diffraction in crystals, imperfect crystals, and amorphous bodies. San Francisco: Freeman; 1963.
   Google Scholar
• Leadbetter AJ. Structural studies of nematic, smectic A and smectic C phases. In: Luckhurst GR, Gray GW, editors. The molecular physics of liquid crystals. London: Academic Press; 1979. p. 285–316.
   Google Scholar
• Vainshtein BK. Diffraction of X-rays by chain molecules. Amsterdam: Elsevier; 1966.
   Google Scholar
• Leadbetter AJ, Richardson RM, Colling CM. The structure of a number of nematogens. J Phys. 1975;36:C1-37−43.
   Google Scholar
• van den Pol E, Petukhov AV, Thies-Weesie DME, et al. Experimental realization of biaxial liquid crystal phases in colloidal dispersions of boardlike particles. Phys Rev Lett. 2009;103:258301. doi:10.1103/PhysRevLett.103.258301.
   PubMed Web of Science ®Google Scholar
• van den Pol E, Petukhov AV, Thies-Weesie DME, et al. Uniaxial and biaxial liquid crystal phases in colloidal dispersions of board-like particles. Liq Cryst. 2010;37:641–651. doi:10.1080/02678291003798164.
   Web of Science ®Google Scholar
• Niori T, Sekine T, Watanabe J, et al. Distinct ferroelectric smectic liquid crystals consisting of banana shaped achiral molecules. J Mater Chem. 1996;6:1231. doi:10.1039/jm9960601231.
   Web of Science ®Google Scholar
• Takezoe H, Takanishi Y. Bent-core liquid crystals: their mysterious and attractive world. Jpn J Appl Phys. 2006;45:597−625. doi:10.1143/JJAP.45.597.
   Web of Science ®Google Scholar
• Teixeira PIC, Masters AJ, Mulder BM. Biaxial nematic order in the hard-boomerang fluid. Mol Cryst Liq Cryst. 1998;323:167–189. doi:10.1080/10587259808048440.
   Web of Science ®Google Scholar
• Champ PJ, Allen MP, Masters AJ. Theory and computer simulation of bent-core molecules. J Chem Phys. 1999;111:9871. doi:10.1063/1.480324.
   Web of Science ®Google Scholar
• Bates MA, Luckhurst GR. Biaxial nematic phases and V-shaped molecules: a Monte Carlo simulation study. Phys Rev E. 2005;72:051702. doi:10.1103/PhysRevE.72.051702.
   PubMed Web of Science ®Google Scholar
• Berardi R, Zannoni C. Do thermotropic biaxial nematics exist? A Monte Carlo study of biaxial Gay–Berne particles. J Chem Phys. 2000;113:5971–5979. doi:10.1063/1.1290474.
   Web of Science ®Google Scholar
• Bates MA. Bent core molecules and the biaxial nematic phase: a transverse dipole widens the optimal angle. Chem Phys Lett. 2007;437:189–192. doi:10.1016/j.cplett.2007.02.025.
   Web of Science ®Google Scholar
• Dingemans TJ, Samulski ET. Non-linear boomerang-shaped liquid crystals derived from 2,5-bis(p-hydroxyphenyl)-1,3,4-oxadiazole. Liq Cryst. 2000;27:131–136. doi:10.1080/026782900203308.
   Web of Science ®Google Scholar
• Han J. 1,3,4-Oxadiazole based liquid crystals. J Mater Chem C. 2013;1:7779–7797. doi:10.1039/c3tc31458h.
   Web of Science ®Google Scholar
• McMillan WL. Measurement of smectic-A-phase order-parameter fluctuations in the nematic phase of p-n-octyloxybenzylidene-p’-toluidine. Phys Rev A. 1973;7:1673–1678. doi:10.1103/PhysRevA.7.1673.
   Web of Science ®Google Scholar
• De Vries A. Evidence for the existence of more than one type of nematic phase. Mol Cryst Liq Cryst. 1970;10:31–35. doi:10.1080/15421407008083484.
   Web of Science ®Google Scholar
• De Vries A. X-ray photographic studies of liquid crystals I. A cybotactic nematic phase. Mol Cryst Liq Cryst. 1973;20:119–236. doi:10.1080/15421407308083307.
   Web of Science ®Google Scholar
• McMillan WL. Measurement of smectic-phase order parameter fluctuations in the nematic phase of heptyloxyazoxybenzene. Phys Rev A. 1973;8:328–331. doi:10.1103/PhysRevA.8.328.
   Web of Science ®Google Scholar
• Safinya CR, Martínez-Miranda LJ, Kaplan M, et al. High-resolution X-ray scattering study of the nematic-to-smectic-C transitions in 8S5−7S5 mixtures. Phys Rev Lett. 1983;50:56–59. doi:10.1103/PhysRevLett.50.56.
   Web of Science ®Google Scholar
• De Vries A. X-ray diffraction studies of the skewed cybotactic nematic phase: a review of the literature. J Mol Liq. 1986;31:193–202. doi:10.1016/0167-7322(86)80001-0.
   Web of Science ®Google Scholar
• Francescangeli O, Laus M, Galli G. Structure of the nematic mesophase with cybotactic groups in liquid-crystalline poly(urethane-ester)s. Phys Rev E. 1997;55:481–487. doi:10.1103/PhysRevE.55.481.
   Web of Science ®Google Scholar
• Francescangeli O, Torgova SI, Karamysheva LA, et al. X-ray diffraction study of new banana-shaped 1,2,4-oxadiazoles. 19th International Liquid Crystal Conference; 2002 Jun 30 –Jul 5; Edinburgh: Book of Abstracts; p. 137.
   Google Scholar
• Peláez J, Wilson MR. Atomistic simulations of a thermotropic biaxial liquid crystal. Phys Rev Lett. 2006;97:267801. doi:10.1103/PhysRevLett.97.267801.
   PubMed Web of Science ®Google Scholar
• Peroukidis SD, Vanakaras AG, Photinos DJ. Molecular simulation of hierarchical structures in bent-core nematic liquid crystals. Phys Rev E. 2011;84:010702(R). doi:10.1103/PhysRevE.84.010702.
   Web of Science ®Google Scholar
• Stojadinovic S, Adorjan A, Sprunt S, et al. Dynamics of the nematic phase of a bent-core liquid crystal. Phys Rev E. 2002;66:060701(R). doi:10.1103/PhysRevE.66.060701.
   Web of Science ®Google Scholar
• Domenici V. Dynamics in the isotropic and nematic phases of bent-core liquid crystals: NMR perspectives. Soft Matter. 2011;7:1589–1598. doi:10.1039/C0SM00735H.
   Web of Science ®Google Scholar
• Hong SH, Williams JC, Twieg RJ, et al. Second-harmonic generation in a bent-core nematic liquid crystal. Phys Rev E. 2010;82:041710. doi:10.1103/PhysRevE.82.041710.
   Web of Science ®Google Scholar
• Jang Y, Panov VP, Kocot A, et al. Short-range correlations seen in the nematic phase of bent-core liquid crystals by dielectric and electro-optic studies. Phys Rev E. 2011;84:060701(R). doi:10.1103/PhysRevE.84.060701.
   Web of Science ®Google Scholar
• Nagaraj M, Panarin YP, Manna U, et al. Electric field induced biaxiality and the electro-optic effect in a bent-core nematic liquid crystal. Appl Phys Lett. 2006;96:011106. doi:10.1063/1.3280817.
   Web of Science ®Google Scholar
• Nagaraj M, Merkel K, Vij JK, et al. Macroscopic biaxiality and electric-field-induced rotation of the minor director in the nematic phase of a bent-core mesogen. EPL. 2010;91:66002. doi:10.1209/0295-5075/91/66002.
   Web of Science ®Google Scholar
• Harden J, Mbanga B, Éber N, et al. Giant flexoelectricity of bent-core nematic liquid crystals. Phys Rev Lett. 2006;97:157802.
   Google Scholar
• Bailey C, Fodor-Csorba K, Verduzco R, et al. Large flow birefringence of nematogenic bent-core liquid crystals. Phys Rev Lett. 2009;103:237803. doi:10.1103/PhysRevLett.103.237803.
   PubMed Web of Science ®Google Scholar
• Bailey C, Fodor-Csorba K, Gleeson JT, et al. Rheological properties of bent-core liquid crystals. Soft Matter. 2009;5:3618–3622. doi:10.1039/b907261f.
   Web of Science ®Google Scholar
• Wiant D, Gleeson JT, Éber N, et al. Nonstandard electroconvection in a bent-core nematic liquid crystal. Phys Rev E. 2005;72:041712.
   Web of Science ®Google Scholar
• Zhang C, Gao M, Diorio N, et al. Direct observation of smectic layers in thermotropic liquid crystals. Phys Rev Lett. 2012;109:107802. doi:10.1103/PhysRevLett.109.107802.
   PubMed Web of Science ®Google Scholar
• Wedler W, Hartmann P, Bakowsky U, et al. X-ray investigations in low-molecular-weight glassy mesophases. J Mater Chem. 1992;2:1195−1204. doi:10.1039/jm9920201195.
   Web of Science ®Google Scholar
• Lehmann M, Kang S-W, Köhn C, et al. Shape-persistent V-shaped mesogens – formation of nematic phases with biaxial order. J Mater Chem. 2006;16:4326–4334. doi:10.1039/B605718G.
   Web of Science ®Google Scholar
• Lehmann M, Köhn C, Cruz C, et al. Biaxial nematic mesophases from shape-persistent mesogens with a fluorenone bending unit. Chem Eur J. 2010;16:8275–8279. doi:10.1002/chem.201001214.
   PubMed Web of Science ®Google Scholar
• Figueirinhas JL, Feio G, Cruz C, et al. Nuclear magnetic resonance spectroscopic investigations of phase biaxiality in the nematic glass of a shape-persistent V-shaped mesogen. J Chem Phys. 2010;133:174509. doi:10.1063/1.3496491.
   PubMed Web of Science ®Google Scholar
• Figueirinhas JL, Dong RY. NMR of bent-core nematogens: a mini-review. Magn Reson Chem. 2014;52:614–624. doi:10.1002/mrc.v52.10.
   PubMed Web of Science ®Google Scholar
• Lehmann M, Seltmann J, Auer AA, et al. Synthesis and mesomorphic properties of new V-shaped shape-persistent nematogens containing a thiazole or a thiadiazole bending unit. J Mater Chem. 2009;19:1978–1988. doi:10.1039/b818240j.
   Web of Science ®Google Scholar
• Droulias S, Vanakaras AG, Photinos DJ. Extending the Maier–Saupe theory to cybotactic nematics. Liq Cryst. 2010;37:969–976. doi:10.1080/02678292.2010.488819.
   Web of Science ®Google Scholar