English  |  正體中文  |  简体中文  |  全文筆數/總筆數 : 49194/83570 (59%)
造訪人次 : 7090931      線上人數 : 53
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
搜尋範圍 查詢小技巧:
  • 您可在西文檢索詞彙前後加上"雙引號",以獲取較精準的檢索結果
  • 若欲以作者姓名搜尋,建議至進階搜尋限定作者欄位,可獲得較完整資料
  • 進階搜尋
    請使用永久網址來引用或連結此文件: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/25511


    題名: Ab initio study of the reaction mechanism of singlet and triplet N2O and their intersystem crossing
    作者: 黃德彥;Hwang, Der-yan;Mebel, Alexander M.
    貢獻者: 淡江大學化學學系
    日期: 2000-09-01
    上傳時間: 2009-12-01
    出版者: Elsevier
    摘要: The lowest singlet and triplet potential energy surfaces of N2O and their intersection are studied using various ab initio methods including MP2, QCISD(T), CCSD(T), CASSCF and multireference configuration interaction method (MRCI). On the singlet surface, two local minima are found, linear NNO (A) and cyclic structure D. The latter lies ∼64 Full-size image (<1 K) higher in energy and is separated from the former by a barrier of about 15 Full-size image (<1 K) at the QCISD(T)/6-311+G(3df)//MP2/6-311+G(2d) and CCSD(T)/6-311+G(3df)//B3LYP/6-311G(d) levels. Both A and D can be produced from N2+O(1D) without barrier with exothermicity of 88.3 and 23.9 Full-size image (<1 K), respectively, at QCISD(T)/6-311+G(3df)//MP2/6-311+G(2d). On the triplet surface, no stable bound N2O structure exists although some plateau on the surface is found in the vicinity of the bent structure B, 73–77 Full-size image (<1 K) above linear A at the QCISD(T) and CCSD(T) levels. Singlet–triplet intersections are located both at the bent geometry (B1) with ∠NNO=114∘ and at the linear structure C. The computed energy of C, 60.3 Full-size image (<1 K) at the MRCI(10,9)/6-311+G(3df) level, closely agree with the experimental activation energy for N2O decomposition. C is minimum on the seam of crossing and has higher spin–orbit coupling than those for bent intersection structures. Thus, the spin-forbidden fragmentation N2O(1Σ+)→N2(1Σg+)+O(3P) should occur via structure C as a “transition state”. The calculations demonstrated that the use of QCISD(T), CCSD(T), full-valence active space CASSCF, or MRCI theoretical levels is essential to compute accurate relative energies of B1 and C.
    關聯: Chemical physics 259(1), pp.89-97
    DOI: 10.1016/S0301-0104(00)00212-3
    顯示於類別:[化學學系暨研究所] 期刊論文

    文件中的檔案:

    檔案 描述 大小格式瀏覽次數
    0KbUnknown223檢視/開啟
    index.html0KbHTML25檢視/開啟

    在機構典藏中所有的資料項目都受到原著作權保護.

    TAIR相關文章

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - 回饋