We report the first examples of bent-shaped LC dimers based on a seven-membered bridged stilbene. We synthesized nonylene- and ether-linked cyano-terminated dimers (sC9-tCN and sOC7O -tCN, respectively) and a homologous se-ries of nonylene-linked alkyl-terminated dimers (sC9-tCn) with alkyl carbon atoms n = 1–6. Polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction measurement were employed to investigate the phase-transition behavior and LC phase structures. sC9-tCN and sOC7O-tCN only exhibited a nematic (N) phase, whereas sC9-tCn (n = 1–5) formed both the NTB and N phases. sC9-tC5 additionally formed an uni-dentified X phase from the NTB phase and sC9-tC6 exhibited a smectic A phase from the N phase. The weak dispersion force and intermolecular affinity provided by the terminal al-kyl chains are likely to be preferable to the large dipole–dipole interactions by the cyano termini for the NTB phase formation of the present dimers. The isotropic points of sC9-tCn showed an odd–even oscillation with n, whereas the N–NTB phase transition temperatures were comparable. Remarkably, the NTB stripe textures of sC9-tCn appeared perpendicular to the rubbing direction, and the N–NTB phase transitions exhibited their second-order nature. This study revealed the unique NTB phase properties of the 7-membered bridged stilbene-based LC dimers..
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