Designing\nHighly Ordered Helical and Nonhelical Porous\nCrystalline and Disordered Nonhelical Columnar Liquid Crystalline\nSelf-Organizations

Helical self-organizations are equilibrium\nstructures responsible\nfor the assembly of nonequilibrium and equilibrium living and synthetic\nsystems. Racemic helical columnar systems transform into one-handed\nsystems with the help of enantiomerically rich or pure components.\nRacemic, enantiomerically rich, and enantiomerically pure helical\nperiodic arrays of columns are analyzed by oriented fiber X-ray diffraction\n(XRD). With few exceptions, highly ordered helical 3-D organizations\nas generated from homochiral columns cannot be obtained from achiral,\nracemic, or enantiomerically rich helical columns. Here, we report\nan unprecedented class of nonhelical porous ordered, disordered nonhelical\ncolumnar liquid crystalline (LC) self-organizations and columnar liquids\nconstructed from AB<sub>4</sub> to AB<sub>9</sub> isomeric terphenyls\nby molecular design unwinding of a 3-D helical organization. A library\nof 16 nonhelical porous ordered, disordered columnar and four liquids\nwas designed by employing as a model a closely related achiral AB<sub>4</sub> <i>meta</i>-terphenyl, which self-organizes one\nof the most perfect synthetic ordered columnar hexagonal helices known.\nA general molecular mechanism to unwind highly ordered 3-D helices\ninto nonhelical porous columnar ordered LCs and liquids was elaborated\nto design this transformation, which provided unprecedented nonequilibrium\nsynthetic systems. This methodology is expected to be general for\ntransformation of helical macromolecular and supramolecular organizations\ninto nonhelical crystals, LCs, and liquids.