Bergman Clusters Related to Bulk Amorphous Alloys and Quasi-crystals

The fcc Zr₂Ni and MgCu₂-type phases, as primary crystallization phases from some bulk amorphous alloys, have similar Bergman clusters in the first-two-shell atomic arrangement, which also appears in the hp MgZn₂-type Laves phase coexisting with icosahedral quasicrystals in the TiZrNi system. Therefore, Bergman cluster may be a bridge linking bulk amorphous alloys and quasicrystals. The stability of the Bergman clusters Zr₃₁Ni₁₄, Mg₃₁Cu₁₄ and Mg₁₈Zn₂₇ can be reflected by density of states at the Fermi level and distribution of charge density on the plane of (100) calculated by local density functional theory.