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Published on: June 8, 2016
[Validation of the crystal structure of medicinal realgar in China]
Zhi-Jie Zhang1, Qun Zhou, Jing-Zhi Wei
1Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China. zzjtcm@126.com
Abstract:
The crystal structure of medicated realgar in China was validated as alpha-As4 S4 by X-ray diffraction and Raman spectroscopy in the present paper. Ten batches of medicinal realgar were analyzed including realgar ore, medicinal realgar powder, and prepared Chinese medicine. Identification of two As4 S4 polymorphs confirmed that the crystal structure of medicated realgar in China is alpha-As4 S4. Studies on 18 batches of preparative realgar powder showed that processing of realgar can not change the crystal structure of realgar.
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