Structural study of F-type iclsahedral quasicrystals and related compounds in Al-transition metal alloys

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400354
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Tohoku University
• Principal Investigator: Fujita Nobuhisa 東北大学, 多元物質科学研究所, 助教 (70431468)
• Co-Investigator(Renkei-kenkyūsha): TAKAKURA HIROYUKI 北海道大学, 工学研究科, 准教授 (30284483) ; TSAI AN-PANG 東北大学, 多元物質科学研究所, 教授 (90225681)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 準結晶 / 近似結晶 / クラスタ / カノニカルセル / 準周期タイリング

Outline of Final Research Achievements

Although more than 30 years have passed since quasicrystals were discovered, their structural details have remained to be unclarified to a large extent posing one of the greatest mysteries in materials science. In order to elucidate the structure of Al-based icosahedral quasicrystals, we first aim at searching for novel approximant phases, namely crystals with similar local structures to that of the quasicrystals. Then we attempt to analyze the structure of new approximants using single-crystal X-ray diffraction to extract any information regarding the structural propserties of the quasicrystals. Overall, these attempts culminate in the discoveries of a few novel approximant crystals, whereas their structures turn out to be composed of two kinds of clusters forming a dense packing. We also propose a new theoretical model describing the arrangement of the clusters in the quasicrystals.

Free Research Field

物性理論