Microphysical derivation of the Canham--Helfrich free-energy density

Brian Seguin; Eliot Fried

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arXiv · 1211.0880

Microphysical derivation of the Canham--Helfrich free-energy density

Brian Seguin·Eliot Fried

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Abstract

The Canham--Helfrich free-energy density for a lipid bilayer has drawn considerable attention. Aside from the mean and Gaussian curvatures, this free-energy density involves a spontaneous mean-curvature that encompasses information regarding the preferred, natural shape of the lipid bilayer. We use a straightforward microphysical argument to derive the Canham--Helfrich free-energy density. Our derivation (i) provides a justification for the common assertion that spontaneous curvature originates primarily from asymmetry between the leaflets comprising a bilayer and (ii) furnishes expressions for the splay and saddle-splay moduli in terms of derivatives of the underlying potential.

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Brian Seguin, Eliot Fried. 2013-01-19. Microphysical derivation of the Canham--Helfrich free-energy density. https://arxiv.org/abs/1211.0880

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