氯酸钠结晶过程中的手性对称破损特性(英文)

CHIRAL SYMMETRY BREAKING CHARACTERISTIC DURING THE PROCESS OF SODIUM CHLORATE CRYSTALLIZATION

采用水溶法生长了NaClO3晶体(完成10个不同组别的100次结晶实验,每个组别循环次数均为1–10次),研究了NaClO3晶体手性对称破损,探讨了晶体成核和生长过程中手性对称破损的温度循环效应。实验结果表明:随着循环次数从1～10次的递增,该晶体的对映异构体过剩(crystal enantiomeric excess,CEE)从0.81增加到0.97。同时,每一组别中CEE的数值分布则从较宽范围的(0.47～1)改变为较窄范围的(0.92～1)。结晶温度的升–降反复循环,对于NaClO3晶体成核和生长过程中的手性对称破损起着非常重要的作用。此方法可应用于对映异构体的结晶提纯。

The aqueous solution method of crystal growth was used to study the crystallization of NaClO3, focusing on the chiral symmetry breaking characteristic. Ten groups of crystal growth experiments were conducted; in each group, about 10 runs of crystallization were performed. The effect of the temperature recycling on the chiral symmetry breaking during nucleation and crystal growth of NaClO3 was investigated. The experimental results show that the crystal enantiomeric excess （CEE） increases from 0.81 to 0.97 with the variety of cycle times from 1 to 10, and at the same time, the CEE distribution range often crystallizations of every group changes obviously from broad （0.47-1） to narrow （0.92-1）. The experimental results also indicate that the ＂up-down＂ temperature recycling plays a very important role in chiral symmetry breaking during crystallization of NaClO3. This method might be useful in enhancing the enantiomeric purity of chiral crystals in crystallization.