Schröder-Turk, G. E. and Mickel, W. and Schröter, M. and Delaney, G. W. and Saadatfar, M. and Senden, T. J. and Mecke, K. and Aste, T. (2010) Disordered spherical bead packs are anisotropic. EPL (Europhysics Letters), 90 (3). p. 34001. ISSN 0295-5075. (Full text available)
Investigating how tightly objects pack space is a long-standing problem, with relevance for many disciplines from discrete mathematics to the theory of glasses. Here we report on the fundamental yet so far overlooked geometric property that disordered mono-disperse spherical bead packs have significant local structural anisotropy manifest in the shape of the free space associated with each bead. Jammed disordered packings from several types of experiments and simulations reveal very similar values of the cell anisotropy, showing a linear decrease with packing fraction. Strong deviations from this trend are observed for unjammed configurations and for partially crystalline packings above 64%. These findings suggest an inherent geometrical reason why, in disordered packings, anisotropic shapes can fill space more efficiently than spheres, and have implications for packing effects in non-spherical liquid crystals, foams and structural glasses.
|Divisions:||Faculties > Science Technology and Medical Studies > School of Physical Sciences > Functional Materials Group|
|Depositing User:||Tomaso Aste|
|Date Deposited:||20 Mar 2012 16:24|
|Last Modified:||28 Mar 2012 09:02|
|Resource URI:||http://kar.kent.ac.uk/id/eprint/29169 (The current URI for this page, for reference purposes)|