過去のセミナー・講演
第20回現代化学ゼミナール(The 20th Frontier Chemistry Seminar)（プロジェクト・ゼミナール）
[日時] 平成20年1月10日（木）15時00分～16時30分まで
[場所] 理学部2号館3階C329講義室
[講師] Professor Chong Zheng（Department of Chemistry, the Northern Illinois University, Dekalb, Illinois, U.S.A.）
[演題] Synthesis, Structures and Physical Properties of Reduced Rare Earth Metal Halide
Abstract: Rare earth halide compounds are of great interest because of their applications as magnetic materials. Many of them can be classified as reduced halides. One of the most remarkable chemical features of these halides is their hosting capability. At the center of a rare-earth metal octahedron or trigonal prism, a variety of interstitials with vastly different electronic configurations can be accommodated. These guests include H, B, Al, Ga, C, Si, Ge, N, P, As, Sb to transition metals such as Mn, Fe, Co, Ni, Ru, Os, Rh, Ir and Pt. Recently, we have being exploring those compounds characterized by high metal-to-nonmetal atomic ratios. In these compounds, there exist many components typical of intermetallic structures such as the two-dimensional CuAl2 and U3Si2 type nets. Some of these compounds, such as Ln4Ga5Br2 and La3GaBr3, are remarkably stable against oxidation and hydrolysis to which reduced rare-earth halides are usually vulnerable. Chemical bonding in these compounds will also be discussed.
[場所] 理学部2号館3階C329講義室
[講師] Professor Chong Zheng（Department of Chemistry, the Northern Illinois University, Dekalb, Illinois, U.S.A.）
[演題] Synthesis, Structures and Physical Properties of Reduced Rare Earth Metal Halide
Abstract: Rare earth halide compounds are of great interest because of their applications as magnetic materials. Many of them can be classified as reduced halides. One of the most remarkable chemical features of these halides is their hosting capability. At the center of a rare-earth metal octahedron or trigonal prism, a variety of interstitials with vastly different electronic configurations can be accommodated. These guests include H, B, Al, Ga, C, Si, Ge, N, P, As, Sb to transition metals such as Mn, Fe, Co, Ni, Ru, Os, Rh, Ir and Pt. Recently, we have being exploring those compounds characterized by high metal-to-nonmetal atomic ratios. In these compounds, there exist many components typical of intermetallic structures such as the two-dimensional CuAl2 and U3Si2 type nets. Some of these compounds, such as Ln4Ga5Br2 and La3GaBr3, are remarkably stable against oxidation and hydrolysis to which reduced rare-earth halides are usually vulnerable. Chemical bonding in these compounds will also be discussed.