Abstract: A cycloheptane derivative as represented by formula (I), and preparation method and use thereof; the compound has photostability and thermostability, wide nematic phase and liquid crystalline state temperature range, and good low-temperature intersolubility, and particularly has low rotary viscosity ?1 and good dielectric anisotropy (??>0).

Abstract: The invention relates to liquid-crystalline compounds of the formula (I) having a —CF2O— bridge. The invention also relates to liquid-crystalline media prepared therewith and to liquid-crystal display devices (LC displays) containing these media. This kind of compounds has the excellent characteristics including a large dielectric anisotropy, fast response time and high clearing point, and good miscibility at low temperature in the same time which has important significance in new TFT LC mixture.

Abstract: The invention relates to liquid-crystalline compounds of the formula (I) having a —CF20- bridge. The invention also relates to liquid-crystalline media prepared therewith and to liquid-crystal display devices (LC displays) containing these media. This kind of compounds has the excellent characteristics including a large dielectric anisotropy, fast response time and high clearing point, and good miscibility at low temperature in the same time which has important significance in new TFT LC mixture.

Abstract: Disclosed is a liquid crystal compound. The compound has a general structural formula as shown by formula I. Such a compound has good thermal and UV stability, large positive dielectric anisotropy ??, and can achieve a low threshold voltage when used in optics, thereby having great significance to the fast response of display devices, and therefore being very suitable for formulating a liquid crystal mixture. A liquid crystal mixture containing such a liquid crystal unit can be applied to various display devices, and is especially suitable for TN-TFT and STN display devices, but can also be used in IPS (in-plane switching) and VA (vertically aligned) display devices.