2012/03/27 by Mohammad Arif Kamal, Antara Pal, Kamal, Md. Arif +5
Biochemistry, Genetics and Molecular Biology · Engineering · Physics and Astronomy · #FOS: Physical sciences #Lipid Membrane Structure and Behavior #Nanopore and Nanochannel Transport Studies #Soft Condensed Matter (cond-mat.soft) #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.1203.5899
openalex publication_date 2012/03/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The structure of the ripple phase of phospholipid membranes remains poorly understood in spite of a large number of theoretical studies, with many experimentally established structural features of this phase unaccounted for. In this article we present a phenomenological theory of phase transitions in single- and two-component achiral lipid membranes in terms of two coupled order parameters -- a scalar order parameter describing \it lipid chain melting, and a vector order parameter describing the \it tilt of the hydrocarbon chains below the chain-melting transition. This model reproduces all the salient structural features of the ripple phase, providing a unified description of the phase diagram and microstructure. In addition, it predicts a variant of this phase which does not seem to have been experimentally observed. Using this model we have calculated generic phase diagrams of two-component membranes. We have also determined the phase diagram of a two-component lipid membrane from x-ray diffraction studies on aligned multilayers. This phase diagram is found to be in good agreement with that calculated from the model.