Investigation on Structure and Bonding of As_4S_4 Isomers |
| |
Institution: | School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China;School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China;School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China;School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China |
| |
Abstract: | Mineral medicine, especially those containing heavy metals, is one of the characteristics of traditional Chinese medicine. A famous mineral medicine, realgar, containing heavy metal arsenic with a chemical formula of As_4S_4, has the function of detoxification, killing bacteria and viruses, and eliminating dampness and phlegm. Different As_4S_4 isomers are likely to have different drug effects and pharmacological actions. Therefore, it is of great scientific significance to find more stable As_4S_4 isomers. In view of this, ab initio molecular orbital theory and density functional theory(DFT) have been used to study ten isomers of As_4S_4 at the B3LYP/6-31 G*, B3LYP/6-311+G*, B3LYP/6-311+G(3 df, 2 p) and MP2/(6-311+G*, LanL2 MB) levels of theory. In addition to the two isomers having been studied previously, eight new isomers were investigated in the present paper. All the ten As_4S_4 isomers were proved to be true local minima on their potential energy surfaces. The calculated NICS values and molecular orbital analyses showed that, the D_(2d) symmetric As_4S_4, isomer 1, may be s-aromatic. The study proves that ten As_4S_4 isomers are stable thermodynamically, and are highly desirable for the future theoretical study of realgar. |
| |
Keywords: | |
本文献已被 CNKI 万方数据 等数据库收录! |
|