Explanation

The form of a substance with a periodic structure composed of organic molecules as the basic units is called. The commonly used growth methods include solution precipitation method and physical gas phase transfer method. The solution method is to dissolve crystal raw materials in a certain solvent and take certain measures to make the crystal molecules in the solvent reach supersaturated state, such as solution cooling or evaporation, so as to precipitate crystals; In the physical vapor transport method, crystal raw materials sublimate in the heating area with higher temperature. Driven by the carrier gas, crystal molecules are transported to the growth region with lower temperature. At this time, the crystal molecules are in the supersaturated state in the gas phase, and then crystallize. Compared with inorganic crystal, organic crystal have the following characteristics: ① the molecular structure of organic crystal is more complex; ② It is much softer than inorganic crystal; ③ It has the characteristics of high efficiency and fast response in interactive functional effects such as light, electricity, and magnetism; ④ Poor thermal stability, low melting point and boiling point. At present, the main applications are: organic nonlinear optical crystal (frequency conversion crystal, electro-optic crystal, etc.); Organic electrical functional crystal (conductive crystal, photoconductive crystal, phot, etc.).

Classification