Local atomic structiure and electron/proton transport properties in Zirconium-based amorphous alloy

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560802
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical properties of metals
• Research Institution: Shizuoka University
• Principal Investigator: FUJIMA Nobuhisa 静岡大学, 工学研究科, 教授 (30219042)
• Co-Investigator(Kenkyū-buntansha): HOSHINO Toshiharu 静岡大学, 大学院工学研究科, 教授 (70157014)
• Co-Investigator(Renkei-kenkyūsha): FUKUHARA Mikio 東北大学, 未来科学技術共同センター, 准教授 (30400401) ; MATSUURA Makoto 東北大学, 金属材料研究所, 特別教育研究教員 (40042262)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 第一原理計算 / Ni-Zr-Nbアモルファス合金 / 局所構造 / 水素吸蔵 / 最低エネルギーパス

Outline of Final Research Achievements

Ni-Zr-Nb amorphous alloys with small content of hydrogen,are exposed to anomalous electrial transport phenomena such as the Coulomb-blockade oscillation in which an electrical charge (proton) tunnels between quantum dots.
In the present work, with the first principles calculation, we proposed a local structural model for the Ni-Zr-Nb amorphous alloy by optimizing the atomic structures of the Ni48Zr40Nb24 cell which consist of icosahedral Ni5Zr5Nb3 clusters and vacancy area. We also identified energetically favorable H-atom sites in the local structure, and find that a H atom is favorably located not at tetrahedral sites in the icosahedral cluster but at octahedral sites in the region of inter-cluster. Furthermore, we explored the minimum energy pass for a H atom in the Ni-Zr-Nb amorphous alloy from an energetically favorable site to another site through the local structures , in which a H-atom feels potential barriers corresponding to a kind of quantum do.

Free Research Field

物性理論，計算物理