کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1340554 | 979740 | 2006 | 7 صفحه PDF | دانلود رایگان |
Micelle formation of surface active CrIII complexes of the type cis-[Cr(en)2(C12H25NH2)X]2+ (where X = F−, Cl−, Br−) have been studied in n -alcohol and in formamide at different temperatures by conductance measurements. Standard Gibbs free energy changes (ΔGmic0), enthalpies (ΔHmic0) and entropies (ΔSmic0) of micelle formation have been determined by studying the variation of the critical micelle concentration (CMC) with temperature. Critical micelle concentrations have also been measured as a function of percentage concentration of alcohol added. It is suggested that alcohol addition leads to an increase in formamide penetration into the micellar interface that depends on the alcohol chain length. The results are discussed in terms of increased hydrophobic effect (solvophobic interaction), dielectric constant of the medium, the chain length of the alcohols and the surfactant in the solvent mixture.
The critical micelle concentration (cmc) of three kinds of metallosurfactants of the type cis-halogeno(dedocylamine)bis(ethylenediamine)chromium(III) have been studied in n-alcohol and formamide mixtures at different temperatures by the electrical conductivity method. Specific conductivity data (at 293–313 K) served for the evaluation of temperature dependent cmc values and thermodynamic parameters such as ΔGm0,ΔHm0andΔSm0.Figure optionsDownload as PowerPoint slide
Journal: Polyhedron - Volume 25, Issue 12, 21 August 2006, Pages 2452–2458