Accepted Wednesday Nov 04, 2009
We report the discovery of a binary icosahedral phase in a Sc-Zn alloy obtained through solution-growth, producing millimeter-sized, facetted, single grain, quasicrystals that exhibit different growth morphologies, pentagonal dodecahedra and rhombic triacontahedra, under only marginally different growth conditions. These two morphologies manifest different degrees of quasicrystalline order. The discovery of i- Sc12Zn88 suggests that a reexamination of binary phase diagrams at compositions close to crystalline approximant structures may reveal other binary quasicrystalline phases.