Energy-based structure prediction for d(Al70Co20Ni10)

We use energy minimization principles to predict the structure of a decagonal quasicrystal–d(AlCoNi)–in the cobalt-rich phase. Monte Carlo methods are then used to explore configurations while relaxation and molecular dynamics are used to obtain a more realistic structure once a low-energy configuration has been found. We find five-fold symmetric decagons 12.8?Å in diameter as the characteristic formation of this composition, along with smaller pseudo-five-fold symmetric clusters filling the spaces between the decagons. We use our method to make comparisons with a recent experimental approximant structure model from Sugiyama et al. (K. Sugiyama, S. Nishimura and K. Hiraga, J. Alloy Comp. 342 65 (2002)).