Solution growth of a decagonal quasicrystal and its related periodic crystals in the Al–Ni–Ru system

Abstract

Single crystals, with a typical size of several millimetres, of a decagonal phase with 1.6 nm periodicity in the Al–Ni–Ru system were grown successfully by the solution-growth method. The conditions for crystal growth were that the initial composition was Al₈₀Ni₁₆Ru₄, the taking-out temperature 900–930°C and the cooling rate 2°C h⁻¹. The lattice parameters were a = 0.2764(2) and c = 1.6523(5) nm, and the composition was in a small range around Al_75.2Ni_14.6Ru_10.2. Single crystals of the orthorhombic Al₁₃(Ni, Ru)₄ phase and the monoclinic Al₁₃(Ni, Ru)₄ phase located at the high-Ni end also formed under slightly different conditions.

Keywords:

• decagonal quasicrystal
• crystal growth
• solution growth
• approximant crystal

Acknowledgements

The authors thank Mr. N. Miyazaki for his help in the EMPA analysis. One of the authors (H.T.) is grateful to Prof. S. Lidin for hospitality and help in the use of Xcalibur CCD diffractometer during his visit at Stockholm University. This research was supported by the KAKENHI (No. 21560003) and FY2009 Researcher Exchange Program between JSPS and RSAS.