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通常，氟化物晶体具有较宽的光透过波段，对水的溶解度较低，是作为紫外和红外的最常用的一些重要材料。氟化物的热习性研究无疑对晶体生长是非常重要的。氟化物在大气的不同温度下产生氧化反应，一般最初产生氢氧化物，随着温度的升高最后变成氧化物。即使在真空状态也产生这些化学反应。本文具体总结了氟化物晶体及其原料在不同温度下的化学反应情况，主要归纳如下。（１）ＸＦ２（Ｘ∶Ｃａ，Ｂａ、Ｍｇ等）之类的高纯原料一般都会有不同量的水分，通过差热分析发现，这些氟化物大约在５００℃时，ＸＦ２＋Ｈ２ＯＸ（ＯＨ）２。在约８００℃时，Ｘ（ＯＨ）ＸＯ。（２）我们研究了氟化物晶体生长过程中除氧剂（如ＰｂＦ２）的作用过程。在真空炉内的化学反应比较复杂，反应生成物有，Ｘ（ＯＨ）２，ＸＯ，Ｈ２Ｏ，ＨＦ，ＣＯ２，ＣＯ等，这些生成物在炉内的含量随温度变化各不相同。例如，炉内的Ｈ２Ｏ从常温到１２００℃的含量曲线，主要有两个峰值：一个在５００℃；一个在７００℃。９５０℃时Ｈ２Ｏ含量为零。还有，ＨＦ的含量曲线也呈现二个峰值。（３）氟化物的退火过程中，仍需要严格控制真空炉内气氛，以免晶体氧化而出现严重的光散射体，我们采用ＲＡＤ方法来控制炉内的气氛，得到良好的?
In general, fluoride crystals have a wide band of light transmission and low solubility in water and are the most commonly used important materials for ultraviolet and infrared. The study of the thermal properties of fluoride undoubtedly is very important for crystal growth. Fluorides produce oxidation reactions at different temperatures in the atmosphere, generally initially producing hydroxides, which eventually become oxides as the temperature increases. These chemical reactions occur even in a vacuum state. This paper summarizes the chemical reaction of fluoride crystals and their raw materials at different temperatures, the main conclusions are as follows. (1) High purity raw materials such as XF2 (X: Ca, Ba, Mg, etc.) generally have different amounts of water. Differential thermal analysis shows that these fluorides have XF2 + H2O X . At about 800 ° C, X (OH) XO. (2) We studied the role of oxygen scavenger (such as PbF2) in the growth of fluoride crystals. The chemical reaction in the vacuum furnace is rather complicated. The reaction products have different contents in the furnace, such as X (OH) 2, XO, H 2 O, HF, CO 2 and CO. For example, the content of H2O in the furnace from normal temperature to 1200 ℃ curve, there are two main peaks: one at 500 ℃; one at 700 ℃. H2O content is zero at 950 ℃. Also, the content curve of HF also shows two peaks. (3) In the process of fluoride annealing, the atmosphere in the vacuum furnace still needs to be strictly controlled so as to prevent the crystal from being oxidized to cause serious light scattering body. We adopt the RAD method to control the atmosphere in the furnace and get a good result.