J. Phys. Colloques
Volume 47, Numéro C3, Juillet 1986International Workshop on Aperiodic Crystals
|Page(s)||C3-351 - C3-360|
J. Phys. Colloques 47 (1986) C3-351-C3-360
NEUTRON DIFFRACTION STUDIES OF THE ICOSAHEDRAL PHASE OF Al-Mn ALLOYSB. MOZER1, J.W. CAHN1, D. GRATIAS2 et D. SHECHTMAN2
1 Center for Material Sciences, NBS, Gaithersburg, MD 20899, U.S.A.
2 C.E.C.M./C.N.R.S., 15, Rue G. Urbain, F-94400 Vitry, France
Powder neutron diffraction studies were performed on three icosahedral alloys of the aluminum manganese system containing 27, 30, and 34 weight percent manganese. Al1 peaks were found at the angles consistent with the icosahedral indexing with a six-dimensional cubic lattice parameter of approximately 0.65 nm that decreased with increasing Mn content. The relative intensities differ significantly from those found for X-rays. The intensities are not consistent with a quasilattice consisting of the 3-dimensional Penrose tiling with a .46 nm edge length along the 5-fold axis. It is consistent with a 1.0 nm edge along the 3- fold axis quasilattice node separation.