A switchable solvatochromic fluorescent dyad can be used to map ordering of lipids in vesicle membranes at a resolution better than the diffraction limit. Combining a Nile Red fluorophore with a photochromic spironaphthoxazine quencher allows the ...
Diffusion Measurements To Understand Dynamics and Structuring in Solutions Involving a Homologous Series of Ionic Liquids
Von Wiley-VCH zur Verfügung gestellt
Self-assembly and organization in solution are demonstrated to be critical in understanding dif- fusion in mixtures containing an ionic liquid. A key discontinu- ity is seen on increasing the car- bon chain length from hexyl to octyl, consistent with the onset of structure in these mixtures.
The self-diffusion coefficients of each of the components in mixtures containing pyridine and each of the homologous series 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imides in acetonitrile were determined using NMR diffusometry (i. e., Pulsed Gradient Spin Echo). The nature of solvation was found to change significantly with the proportion of salt in the mixtures. Increased diffusion coefficients (when corrected for viscosity) for the molecular components were observed with increasing proportion of ionic liquid and with increasing alkyl chain length on the cation. Comparison of the molecular solvents suggests increased interactions in solution of the pyridine with other components of the mixture, consistent with the proposed interactions shown previously to drive changes in reaction kinetics. Discontinuities were seen in the diffusion data for each species in solution across different ionic liquids between the hexyl and octyl derivatives, suggesting a change in the structuring in solution as the alkyl chain on the cation changes and demonstrating the importance of such when considering homologous series.Zum Volltext
Jetzt nächsten Artikel lesen:
Überprüfung Ihres Anmeldestatus ...
Wenn Sie ein registrierter Benutzer sind, zeigen wir in Kürze den vollständigen Artikel.