A biaxial nematic phase with D2h symmetry has the mesogen's long and short transverse axes simultaneously aligned along the two orthogonal directors, n and m, respectively. Low-angle x-ray diffraction measurements in the nematic phase exhibited by three rigid bent-core mesogens clearly reveal its biaxiality. The diffraction results can be readily reproduced by ab initio calculations of molecular form factor assuming short-range positional correlations in the nematic phase with the apex of the core aligned along m.
Liquid Crystals Today
Acharya, Bharat R.; Primak, Andrew; Kumar, Satyendra (2004). The Bent-Core Biaxial Nematic Phase. Liquid Crystals Today 13(1) 191-4. doi: 10.1080/14645180410001697058. Retrieved from https://oaks.kent.edu/article/bent-core-biaxial-nematic-phase