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Updated: Jun 29, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Internal dynamics and optical rotations predicted for O(h)- and O-symmetric cubanes
David A Hrovat1, Christine M Isborn, Bart Kahr
1Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, Univeristy of North Texas, 1155 Union Circle, #305070, Denton, Texas 76203-5017, USA.
Abstract:
B3LYP/6-31G(d) calculations find that cubanes, persubstituted with NO2 or BF2 groups, are predicted to undergo near-barrierless, internal disrotations. However, as a consequence of the intrinsically higher energies of eclipsed conformations for threefold than for twofold rotors, the threshold mechanisms for octamethyl-, octakis(trifluoromethyl)-, octakis(trichloromethyl)-, octakis(tribromomethyl)-, octasilylcubane, and octakis(trichlorosilyl)cubane are calculated to be mono- or conrotation. The cubanes with the larger substituents are predicted to be O-symmetric, resolvable, and thus optically active.
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