Abstract
The equilibrium shapes (ESs) of icosahedral quasicrystals are analyzed for a wide class of lattice models which incorporate finite-range two-body interactions. Completely faceted shapes have been predicted for such models at temperature T=0. We prove that a number of simple shapes cannot be ESs for any model in this class for which the atomic interactions are constrained to be pure-attractive. This extends the result of Ho et al. [Phys. Rev. Lett. 59, 1116 (1987)], who showed that the pentagonal dodecahedron, a shape observed in grains of icosahedral Al-Cu-Fe and Ga-Mg-Zn, is a forbidden shape for pure-attractive models. We then introduce a lattice model for quasicrystals which incorporates mixed attractive and repulsive interactions and show that the possible ESs include the dodecahedron and other previously forbidden shapes.
Original language | English (US) |
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Pages (from-to) | 980-992 |
Number of pages | 13 |
Journal | Physical Review B |
Volume | 39 |
Issue number | 2 |
DOIs | |
State | Published - 1989 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics