Structural variations in local areas of an Al_(70)Ni_(15)Fe_(15) decagonal quasicrystal and the interpretation by the 1-nm column-pair scheme

摘要

Structural variations in local areas such as the star-shaped and butterfly-shaped tiles of a noncentrosymmetric decagonal quasicrystal of Al_(70)Ni_(15)Fe_(15) have been investigated by using the high-angle annular dark-field scanning transmission electron microscope method. It has been demonstrated that the variations of the star-shaped and butterfly-shaped tiles in Al_(70)Ni_(15)Fe_(15) are uniquely decomposed into the 1-nm column-pairs [Saitoh et al., J. Phys. Soc. Jpn. 68 (1999) 2886], which is the basic structural unit of the tau~2-inflated Al_(13)Co_4 approximant.