期刊論文
| 學年 | 88 |
|---|---|
| 學期 | 2 |
| 出版（發表）日期 | 2000-06-01 |
| 作品名稱 | Ab initio study of spin-forbidden unimolecular decomposition of carbon dioxide |
| 作品名稱（其他語言） | |
| 著者 | 黃德彥; Hwang, Der-yan; Mebel, Alexander A. M. |
| 單位 | 淡江大學化學學系 |
| 出版者 | Elsevier |
| 著錄名稱、卷期、頁數 | Chemical physics 256(2), pp.169-176 |
| 摘要 | The results of ab initio G2(MP2), QCISD(T)/6-311+G(3df) and full valence active space CASSCF(16,12)/6-311+G(3df) calculations of the stationary points on the lowest singlet and triplet potential energy surfaces of carbon dioxide and their intersystem crossing show that spin-forbidden unimolecular decomposition of CO2 can proceed by two different mechanisms. The non-collinear channel goes through a C2v-symmetric minimum energy crossing point MSX1 in the vicinity of the bent local minimum 4 in the triplet state. Once on the triplet surface, the molecule has to overcome the barrier of 131.3 kcal/mol at transition state TS3 before yielding the products, Full-size image (<1 K). The collinear channel directly leads from CO21 to the products via linear MSX2. The barrier at MSX2, estimated as ∼135 kcal/mol, is higher than that for the non-collinear channel, but the probability of intersystem crossing for the collinear mechanism is expected to be higher than for the non-collinear channel, since the spin–orbit coupling value for MSX2 (Full-size image (<1 K)) is much higher than that for MSX1 (Full-size image (<1 K)). The two mechanisms of unimolecular decomposition of CO2 are expected to compete with each other and exhibit different mode-specific dynamics. Spin-forbidden fragmentation of CO2 is compared with the fragmentation of the isoelectronic N2O molecule. The mechanisms for the reverse Full-size image (<1 K) and Full-size image (<1 K) reactions are also discussed. |
| 關鍵字 | |
| 語言 | en |
| ISSN | 0301-0104 |
| 期刊性質 | 國內 |
| 收錄於 | |
| 產學合作 | |
| 通訊作者 | |
| 審稿制度 | 否 |
| 國別 | TWN |
| 公開徵稿 | |
| 出版型式 | ,電子版 |
| 相關連結 |
機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/25467 ) |