教師資料查詢 | 類別: 期刊論文 | 教師: 吳慧芬 HUI-FEN WU (瀏覽個人網頁)

標題:Comparison of the orders of gas-phase basicities and ammonium ion affinities of polyethers by the kinetic method and ligand exchange technique
學年82
學期1
出版(發表)日期1993/09/01
作品名稱Comparison of the orders of gas-phase basicities and ammonium ion affinities of polyethers by the kinetic method and ligand exchange technique
作品名稱(其他語言)
著者Wu, H. F.; 吳慧芬; Brodbelt, J. S.
單位淡江大學化學學系
出版者
著錄名稱、卷期、頁數Journal of the American society for mass spectrometry4, pp.718-722
摘要The orders of relative gas-phase basicities and ammonium ion affinities of a series of polyethers obtained by application of the kinetics method and ligand exchange technique are compared to evaluate the discrepancies of results between the two techniques. The order of gas-phase basicities determined by the ligand exchange technique in a quadrupole ion trap agrees with the order established previously by Kebarle using equilibrium methods in a high-pressure mass spectrometer. The order obtained by the kinetic method in a triple quadrupole mass spectrometer varies for the ranking of one polyether (12-crown-4), and this discrepancy is attributed to a difference in the rates of the competing dissociation pathways from the triethylene glycol dimethyl ether/12-crown-4 proton-bound adduct, owing to a substantial variation in the flexibilities of these two ethers. For the order of gas-phase ammonium ion affinities, the kinetic method results agree overall with the ligand exchange results; however, the order of ammonium ion affinities for tetraethylene glycol dimethyl ether and 15-crown-5 could not be differentiated by the ligand exchange method because of the rapidity of ammonium ion transfer between the two polyethers in both directions.
關鍵字
語言英文
ISSN
期刊性質國內
收錄於
產學合作
通訊作者
審稿制度
國別中華民國
公開徵稿
出版型式,電子版
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