Abstract
We have discovered four new approximant phases of the B–Mg–Ru decagonal quasicrystal. Six phases were observed in electron diffraction patterns of B–Mg–Ru alloys prepared at 1673 K from B2xMg(1-x)Ru2(1-x) (x = 0.44–0.48). Two of them are known, B4Mg2Ru5 and B11Mg5Ru13, and the other four are new approximant phases. Their lattice parameters range from a = 0.84 nm to 8.5 nm; some of them can be described with the Fibonacci sequence. We suggest tiling models of these approximants using two subunits of B4Mg2Ru5 and B11Mg5Ru13, ‘hexagon’ and ‘boat’.
Acknowledgment
We are grateful to Mr. T. Itoh for kind guidance and technical support to use TEM at Institute of Engineering Innovation, the University of Tokyo.