Micelle formation of some surface active mixed-ligand cobalt(III) complexes containing one of the chelating ligands ethylenediamine (en), triethylenetetramine (trien), 2,2 bipyridyl (bpy) or 1,10 phenanthroline (phen) as equatorial and with different axial amine ligands (dodecylamine or cetylamine) were synthesized and characterized by IR, NMR, UV-visible electronic absorption spectra and elemental analysis. The critical micelle concentration (CMC) values of these surfactant metal complexes in aqueous solution were obtained from conductance measurements. Specific conductivity data (at 303, 308 and 313 K) served for the evaluation of the temperature-dependent CMC and the thermodynamics of micellization (Δ Gm0, Δ Hm0 and Δ Sm0). © 2006 Elsevier Ltd. All rights reserved.

Santhakumar K

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Arunachalam V

Department of Micro and Nanoelectronics

School of Electronics Engineering

Kumaraguru N

Arumugham M.N.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Polyhedron

The critical micelle concentration (CMC) of surfactant-Cr(III)-dodecylamine complexes of the type cis-α-[Cr(trien)(C 12H 25NH 2)X] 2+ (where trien = triethylenetetramine; X = F -, Cl -, Br -) has been studied in n-alcohol and in formamide at different temperatures, by electrical conductivity measurements. From the CMC values as a function of temperature, various thermodynamic properties have been evaluated: standard Gibbs energy changes (Δ micG 0), standard enthalpy changes (Δ micH 0) and standard entropy changes (Δ micS 0) for micellization. Critical micelle concentrations have also been measured as a function of the percentage composition of alcohol added. The solvent composition dependences of these thermodynamic parameters were determined. It is suggested that alcohol addition leads to an increase in formamide penetration into the micellar interface that depends on the alcohol's chain length. The results are discussed in terms of an increased hydrophobic effect, dielectric constant of the medium, the chain length of the alcohols, and the surfactant in the solvent mixture. © Springer Science+Business Media, LLC 2011.

Journal of Solution Chemistry

Studies on Thermodynamics of Micellization and Solvophobic Interactions of Novel Surfactant–Cr(III) Complexes in Non-aqueous Solvents

The surfactant-Co(III) complexes of the type cis-[Co(en)2AX]2+ (A=Tetradecylamine, X=Cl,Br) were synthesised from corresponding dihalogeno complexes by the ligand substitution method. The critical micelle concentration (CMC) values of these surfactant complexes in aqueous solution were obtained from conductance measurements. The kinetics and mechanism of iron(II) reduction of surfactant-Co(III) complexes, cis-[Co(en)2(C14H29NH2)Cl](ClO4)2 and cis-[Co(en)2(C14H29NH2)Br] (ClO4)2 ions were studied spectrophotometrically in an aqueous acid medium by following the disappearance of Co(III) using an excess of the reductant under pseudo-first-order conditions: [Fe(II)]=0.25moldm -3, [H+]=0.1moldm -3, [μ]=1.0moldm -3 ionic strength in a nitrogen atmosphere at 303, 308 and 313K. The reaction was found to be of second order and showed acid independence in the range [H+]=0.05-0.25moldm -3. The second-order rate constant increased with surfactant-Co(III) concentration and the presence of aggregation of the complex itself altered the reaction rate. The effects of [Fe(II)], [H+] and [μ] on the rate were determined. Activation and thermodynamic parameters were computed. It is suggested that the reaction of [Fe(II)] with Co(III) complex proceeds by an inner-sphere mechanism. © 2010 Taylor &amp; Francis.

Physics and Chemistry of Liquids

Studies on synthesis, determination of CMC values, kinetics and the mechanism of iron(II) reduction of surfactant–Co(III)–ethylenediamine complexes in aqueous acid medium

The electron-transfer kinetics of the ionic surfactant complex cis-chloro/bromo(cetylamine)bis(ethylenediamine)cobalt(III) by iron(II) in aqueous perchlorate medium at μ=1.0 mol·dm-3 ionic strength have been studied at 303, 308 and 313 K by spectrophotometry under pseudo-first-order conditions using an excess of the reductant. The effects of [H+], ionic strength and [Fe2+] on the rate were determined. The reaction was found to be second order and showed to be independence of the acid concentration in the range [H+]=0.05-0.25 mol·dm-3. The second order rate constant increased with surfactant-cobalt(III) concentration and the occurrence of aggregation of the complex itself altered the reaction rate. Activation and thermodynamic parameters have been computed. It is suggested that the reaction of Fe 2+(aq) with the cobal (III) complex proceeds by an inner-sphere mechanism. The critical micelle concentration (CMC) values of these surfactant-metal complexes were obtained in aqueous solution from conductance measurements. Specific conductivity data (at 303, 308 and 313 K) served for the evaluation of the temperature-dependence of the critical micelle concentration (CMC) and the thermodynamics of micellization (ΔG m o,ΔH m o and ΔS m o ). © 2009 Springer Science+Business Media, LLC.

Studies on the Reaction Kinetics and Mechanism of Iron(II) Reduction of the cis-Halogeno(cetylamine)bis(ethylenediamine)cobalt(III) Complex Ion in Aqueous Perchlorate Medium

Surface active mixed-ligand complexes of Cr(III) containing chelating ligands, namely ethylenediamine (en), triethylenetetramine (trien), 2,2-bipyridine (bpy), and 1,10-phenanthroline (phen) with different axial amine ligands (dodecylamine or cetylamine) were synthesized and characterized by UV-Vis, infrared, and NMR spectroscopies and elemental analysis. The magnetic moments (3.6-3.8 B.M.) are close to the spin-only value for a d3 Cr(III) in octahedral symmetry. The critical micelle concentration values of these surfactant metal complexes in aqueous solution were determined as a function of temperature using conductometric technique. Thermodynamics of micellization (ΔGm0, ΔHm0 and ΔSm0) were evaluated. Dodecyl/cetylamine metallosurfactants obtained were tested for antibacterial and antifungal activities having good activities. © 2009 Taylor &amp; Francis.

Journal of Coordination Chemistry

Synthesis, characterization, critical micelle concentration determination, and antimicrobial studies of some complexes of chromium(III) metallosurfactants

Surface active micelle formable surfactant-Cr(III) complexes of the type cis-α-[Cr(trien)(C16H33NH2)X] 2+ (where trien = triethylenetetramine; X = F-, Cl -, Br-) have been studied in n-alcohol and in formamide at different temperatures by conductance measurements. Standard Gibbs energy changes (ΔG o mic), enthalpies (ΔH o mic) and entropies (ΔS o mic) 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 an increased hydrophobic effect, dielectric constant of the medium, the chain length of the alcohols and the surfactant in the solvent mixture. © 2009 Springer Science+Business Media, LLC.

Studies on Hydrophobic Effect and Micelle Formation of Some Surfactant-Cr(III)-Cetylamine Complexes in Non-aqueous Solvents

Kinetics of reduction of the surfactant complex ions, cis-chloro/bromo (dodecylamine)bis(ethylenediamine)cobalt(III) by iron(II) in aqueous solution was studied at 303, 308, and 313 K by spectrophotometry method under pseudo-first-order conditions, using an excess of the reductant. The second-order rate constant remains constant below critical micelle concentration (cmc), but increases with cobalt(III) concentration above cmc, and the presence of aggregation of the complex itself alters the reaction rate. The rate of reaction was not affected by the added [H+]. Variation of ionic strength (μ) influences the reaction rate. Activation and thermodynamic parameters have been computed. It is suggested that the reaction of Fe 2+ (aq) with cobalt(III) complex proceeds by the inner-sphere mechanism. © 2005 Wiley Periodicals.

International Journal of Chemical Kinetics

Kinetics of Fe(II) reduction ofcis-halogeno(dodecylamine) bis(ethylenediamine)- cobalt(III) complex ion in aqueous solutions

A number of mixed ligand cobalt(III)-surfactant coordination complexes of the type cis-[Co(en)2(A)X]2+ and cis-α-[Co(trien)(A)X]2+ (A = Dodecyl or Cetylamine, X = Cl-, Br-, NO2) were synthesized from the corresponding dihalogeno complexes by the ligand substitution method. These compounds form a foam in aqueous solution when shaken. The critical micelle concentration (CMC) values of these surfactant metal complexes in aqueous solution were obtained from conductance measurements. Specific conductivity data (at 303, 308 and 313 K) served for the evaluation of the temperature-dependent critical micelle concentration (CMC) and the thermodynamics of micellization ( Δ Gm0, Δ Hm0 and Δ Sm0). © 2005 Elsevier Ltd. All rights reserved.

Metallomicelles of Co(III) coordination complexes – Synthesis, characterization and determination of CMC values

A number of mixed ligand chromium(III)-surfactant coordination complexes, of the type cis-[Cr(en)2(A)X]2+ and cis-α-[Cr(trien) (A)X]2+ (A = Dodecyl or Cetylamine; X = F-, Cl -, Br-) were synthesized from the corresponding dihalogeno complexes by ligand substitution. These compounds form foam in aqueous solution when shaken. The critical micelle concentration (CMC) values of these surfactant metal complexes in aqueous solution were obtained from conductance measurements. Specific conductivity data (at 303, 308 and 313 K) served for evaluation of the temperature-dependent critical micelle concentration (cmc) and the thermodynamics of micellization (Δ G m 0, Δ H m 0 and Δ S m 0). © Springer 2006.

Fulltext

Transition Metal Chemistry

Metallosurfactants of Chromium(III) Coordination Complexes. Synthesis, Characterization and Determination of CMC Values

Journal of Dispersion Science and Technology

Metallomicellar Catalysis: Phosphodiester Hydrolysis Catalyzed by Cu(II), Zn(II), Ni(II), and Co(II) Complexes of Chelating Pyridyl Donor Ligands in CTAB Micellar Solution

Journal	Data powered by TypesetPolyhedron
Publisher	Data powered by TypesetElsevier BV
ISSN	0277-5387
Open Access	No