Lyotropic mesophases as defects in binary mixtures

Lyotropic mesophases as defects in binary mixtures

2014 The classification of defects in ordered media is applied to the case of binary mixtures. Stable defects must be surfaces, and, in that case, interfaces. For lyotropic systems, a negative surface energy leads to a maximization of the interface area. One thus obtains, with increasing surfactant concentration, micelles, and then liquid crystal phases which must be considered as ordered defec...

Identification of Lyotropic Liquid Crystalline Mesophases

On the Swelling of Bicontinuous Lyotropic Mesophases

The swelling of sponge-like bicontinuous mesophases of bilayers of surfactant (or lipid) in water as a function of dilution is analyzed. Analytic formulae for the swelling are derived assuming ii) constant aggregate thickness and (it) fixed surface area per surfactant molecule at an imaginary surface located within the bilayer. Approximate swelling laws are derived for bicontinuous films and co...

Entropic Behavior of Binary Carbonaceous Mesophases

The Maier-Saupe model for binary mixtures of uniaxial discotic nematogens, formulated in a previous study [1], is used to compute and characterize orientational entropy [2] and orientational specific heat. These thermodynamic quantities are used to determine mixture type (ideal or non-ideal) which arise due to their different intrinsic properties, determined by the molecular weight asymmetry ΔM...

Comprehensive examination of mesophases formed by DMPC and DHPC mixtures.

Mixtures of long- and short-chain phospholipids, specifically 14:0 and 6:0 phosphatidylcholines (DMPC and DHPC), have been used successfully in NMR studies as magnetically alignable substrates for membrane-associated proteins. However, recent publications have shown that the phase behavior of these mixtures is much more complex than originally thought. Using polarized light microscopy and small...