頁籤選單縮合
題 名 | NMR Study of the Ligand Interchange of Hexacyclen and Hexamethylhexacyclen Complexes with Tl狇Ion in 70% Methanol Solution |
---|---|
作 者 | Shamsipur,Mojtaba; Alizadeh,Naader; | 書刊名 | Journal of the Chinese Chemical Society |
卷 期 | 45:2 1998.04[民87.04] |
頁 次 | 頁241-247 |
分類號 | 340 |
關鍵詞 | T1狇; HCY; HMHCY; 70% methanol; Exchange kinetics; NMR; |
語 文 | 英文(English) |
英文摘要 | The exchange kinetics of Tl□ complexes with hexacyclen and hexamethylhexacyclen were studied in 70% methanol solution by proton NMR line-shape analysis. In Tl□-hexacyclen system, a dissociative mechanism is found to be predominant at higher temperatures, while a bimolecular pathway may become more important at lower temperatures In contrast, the Tl□-hexamethylhexacyclen system solely prefers a dissociative exchange mechanism in entire temperature range studied. The corresponding exchange rates and the activation parameters E□, ΔH□, ΔS□ and ΔG□ for the exchange have been determined, and the possible parameters controlling the exchange rates and mechanisms are discussed. |
本系統中英文摘要資訊取自各篇刊載內容。