The First Banana• Pelzl, G.; Wirth, I.; Weissflog, W. "The first 'banana phase' foundin an original Vorländer substance," Liq. Cryst. 2001, 28, 969-972.• Vorländer, D.; Apel, A. Ber.Dtsch. Chem. Ges. 1929, 62, 2831.• Vorländer, D.; Apel, A.; Galka,W. Ber. 1932, 65B, 1101-9.OONNOC2H5NNC2H5OOOO OX ” 184 “ M ” 218.5 “ I (Vorländer)X ” 186 “ B6 ” 224 “ I (Pelzl et al.)Vorländer’s IdeaVorländer, D.; Apel, A.; Galka, W. "The direction of the carbon valences in benzene derivatives.II.," Ber. 1932, 65B, 1101-9.cf. C. A. 24, 1358. p-Phenetoleazoxybenzoic acid (I), calledphenobenzoic acid for short (C. A. 26, 2357; a more detailed descriptionwill be published later), sublimes 205∞, m. 234∞ to a cryst. liquid,seems to be better adapted than any other CO2H acid to thecharacterization of alcs., phenols and amines, not only through the m. ps.of the products it forms but also through their cryst.-liquid (c.-l.)properties. o-, m- and p-C6H4(OH)2 (II) have been esterified with I inorder to correlate the c.-l. properties of the esters with the directions ofthe C-O unions in the 3 isomeric II. As was to be expected, the di-estersof p-II are the most strongly c.-l., those of o- and m-II being much moreweakly c.-l. because of the angle of the C-O unions on the benzene.OHNNC2H5OOOIHOOHo, m, and p IINOBOW B2 Electro-optics4 µmApplied field isperpendicularto the screenCalamitic Chiral Ferro- and Antiferro- LCsSynclinic Ferroelectric SmC*Anticlinic AntiferroelectricSmCA*NOBOW looks AntiferroelectricAFFEFENonsuperposable Mirror Images+-The arrows are all pointing inthe same direction, and thedirector is tilted, giving a C2layer structure. This symmetryis both polar and chiral.znLayer Structure: Spontaneous Nonpolar AND Reflection Symmetry BreakingONRONROOµ=nbRobert Meyer - 1974The SmC* has C2 symmetry,and has a macroscopic dipolemoment.Polar Axis (C2)Chiral MoleculesTilt Plane ≡ Normal to C2 Polar Plane ≡ Contains C2 and zznThe Polar Plane and the Tilt Plane(-) NOBOW Antiferro EO SwitchingAchiral EO responseof the green stripes+--+Superposable Mirror Images!Macroscopic RacemateStructure of the Achiral Antiferro PhaseAchiral EO in the Green
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