Explanation
According to temperature and the material properties of liquid crystals, liquid crystals can be in one of the many liquid crystal phases, and nematic phase is one of the most common phase states of liquid crystals. The substance that presents nematic phase at a certain temperature and concentration range is called nematic liquid crystal. In the nematic phase, rod-shaped molecules do not have a certain positional order, but they self adjust to form a long-range order through the roughly parallel direction of their long axis. Therefore, although the arrangement of the barycentres of rod-shaped molecules is disordered and can flow freely in the liquid crystal, they still maintain a basically parallel arrangement with each other. Under the action of external magnetic or electric fields, molecules are easily affected and form a certain arrangement. Most are uniaxial: molecules have only one longer axis and two other shorter but phase axes. However, a few nematic liquid crystal are biaxial: such molecules are oriented not only to their long axis, but also to their secondary long axis.
Classification
Information materials -> Photosensitive and display materials -> Photosensitive and display materials