Defects in crystalline packings of twisted filament bundles. II. Dislocations and grain boundaries.

  title={Defects in crystalline packings of twisted filament bundles. II. Dislocations and grain boundaries.},
  author={Amir Azadi and Gregory M. Grason},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  volume={85 3 Pt 1},
  • A. Azadi, G. Grason
  • Published 29 December 2011
  • Materials Science, Medicine, Physics
  • Physical review. E, Statistical, nonlinear, and soft matter physics
Twisted and ropelike assemblies of filamentous molecules are common and vital structural elements in cells and tissues of living organisms. We study the intrinsic frustration occurring in these materials between the two-dimensional organization of filaments in cross section and out-of-plane interfilament twist in bundles. Using nonlinear continuum elasticity theory of columnar materials, we study the favorable coupling of twist-induced stresses to the presence of edge dislocations in the… 
Defects in crystalline packings of twisted filament bundles. I. Continuum theory of disclinations.
  • G. Grason
  • Materials Science, Physics
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  • 2012
The effective theory of multiple disclination defects in the cross section of bundle with a fixed twist is derived and it is shown that above a critical degree of twist, one or more fivefold disclinations is favored in the elastic energy ground state.
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