用SAC-CI/6-311g方法计算了二甲基硅酮[DMS,(CH3)2SiO]的单重态和其激发态,得到基态为X1A1,其3个低激发态依次为1A2、1A1和1B1,其电子光谱都出现在紫外可见区,这是二甲基硅酮(DMS)的独特之点.根据群的对称性原理,指出在二甲基硅酮[DMS,(CH3)2SiO]中(图1),同时离解5H和8H,是对称性最许可的.计算出同时离解3C-5H和4C-8H时的离解能和同时离解键1Si-3CH3和1Si-4CH3时的离解能,由基H和CH3会发生自由基反应,这与脉冲辐射的紫外可见光谱无结构[3]的实验相合.可以预计在离解气体产物中,甲烷CH4成分最多,其次为H2,乙烷C2H6最少,文献[1]的实验正是如此.
参考文献
[1] | Wei Huang;Fu Yibei .[J].Radiation Physics and Chemistry,2002,64:229. |
[2] | Chaudhry A N;Billingham N C .[J].Polymer Degradation and Stability,2001,73:505. |
[3] | Szadkowska-Nicze M;Kulpinski J;Michalska Z M et al.[J].Journal of Photochemistry and Photobiology A:Chemistry,1998,117:153. |
[4] | 陈晓军,罗顺忠,蒋树斌,黄玮,高小铃,马美仲,朱正和.外场下二甲基硅酮双自由基的从头计算研究[J].原子与分子物理学报,2004(02):203-209. |
[5] | Hasegawaa J;Eharaa M;Nakatsuji H .[J].Chemical Physics,1998,230:23. |
[6] | Nakatsuji H .[J].Journal of Chemical Physics,1998,9:7179. |
[7] | Nakatsuji H;Hirao K .[J].Journal of Chemical Physics,1978,68:2O53. |
[8] | Nakatsuji H .[J].Chemical Physics Letters,1979,67:329. |
[9] | Nakatsuji H .[J].Acta Chimica Academiae Scientiarum Hungaricae,1992,129:719. |
[10] | Nakatsuji H.Computational Chemistry-Reviews of Current Trends[M].Singapore,World Scientific,1997:62. |
[11] | Nakajima T;Nakatsuji H .[J].Chemical Physics,1999,242:177. |
[12] | Zhu Z H .[J].Science in China(Series G),2007,50:581. |
[13] | Pearson R G.Symmetry Rules for Chemical Reactions[M].USA,A Wily-Interscience Publication,1976:150. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%