Diffusion of a Highly Charged Supramolecular Assembly: Direct Observation of Ion Association in Water

详细信息    查看全文

• 作者：Michael D. Pluth ; Bryan E. F. Tiedemann ; Herman van Halbeek ; Rudi Nunlist ; Kenneth N. Raymond
• 刊名：Inorganic Chemistry
• 出版年：2008
• 出版时间：March 3, 2008
• 年：2008
• 卷：47
• 期：5
• 页码：1411 - 1413
• 全文大小：317K
• 年卷期：v.47,no.5(March 3, 2008)
• ISSN：1520-510X

文摘

The diffusion coefficient of the self-assembled supramolecular cluster [Ga₄L₆]¹²⁻ depends on the cationic counterions in solution. Diffusion coefficients were determined using the pulsed-gradient spin–echo ¹H NMR method and fit using nonlinear least-squares refinement. Saturation studies revealed a small number of ion-association sites on the exterior of the assembly and the direct observation of ion association in water. The addition of excess alkali-metal cations displaces the ion-associated hydrophobic tetraalkylammonium cations. Comparisons between tetraethyl- and tetrapropylammonium show a preference for ion association with the more hydrophobic cation.