Unusually Dense Crystal Packings of Ellipsoids

Aleksandar Donev,^1,2 Frank H. Stillinger,⁴P. M. Chaikin,^2,3 and Salvatore Torquato^1,2,4

¹Program in Applied and Computational Mathematics, Princeton University, Princeton, New Jersey 08544, USA
²Materials Institute, Princeton, New Jersey 08544, USA
³Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
⁴Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA

(Received 28 March 2004; published 23 June 2004. Phys. Rev. Letters 92, 255506 (2004))

Abstract:

In this Letter, we report on the densest-known packings of congruent ellipsoids. The family of new packings consists of crystal arrangements of spheroids with a wide range of aspect ratios, and with density always surpassing that of the densest Bravais lattice packing 0.7405. A remarkable maximum density of 0.7707 is achieved for maximal aspect ratios larger than , when each ellipsoid has 14 touching neighbors. Our results are directly relevant to understanding the equilibrium behavior of systems of hard ellipsoids, and, in particular, the solid and glassy phases. ©2004 The American Physical Society