Lyotropic Liquid-Crystalline Mesophases of [Zn(H₂O)₆](NO₃)₂−C₁₂EO₁₀−CTAB−H₂O and [Zn(H₂O)₆](NO₃)₂−C₁₂EO₁₀−SDS−H₂O Systems

Abstract

The mixture of two surfactants (C12EO10-CTAB and C12EO10-SDS) forms lyotropic liquid-crystalline (LLC) mesophases with [Zn(H2O)6](NO3)2 in the presence of a minimum concentration of 1.75 H2O per C12EO10. The metal ion/C12EO10 mole ratio can be increased up to 8.0, which is a record high metal ion density in an LLC mesophase. The metal ion concentration can be increased in the medium by increasing the CTAB/C12EO10 or SDS/C12EO10 mole ratio at the expense of the stability of the LLC mesophase. The structure and some thermal properties of the new mesophase have been investigated using XRD, POM, FTIR, and Raman techniques.