Structure-Composition-Property Relationships in Complex Intermetallic Phases: Experimental and Theoretical Studies

该项目旨在利用实验和理论来系统地寻找具有潜在有趣的物理和化学性质的新金属间化合物。 由于组成的细微变化会对金属间化合物的结构和物理性质产生巨大影响，因此电子结构的理论计算将在这些相的完整和系统研究中发挥重要作用。 新多元化合物的合成和详细表征将涉及（i）正电性碱金属、碱土金属或稀土金属;（ii）过渡金属;和（iii）第13族元素（铝、镓、铟）或镁或锰。 选择第13族元素是因为它们在元素周期表中的位置处于金属和非金属之间的边界。 这些元素的组合有望创造出美丽的复杂结构，包括相互连接和相互渗透的原子簇，这将允许彻底研究组成，结构，性质和化学键之间的关系。将合成和表征可能用作热电材料或预期对环境无害的强高温导体的材料。 该项目将涉及化学，物理和材料科学的学生通过爱荷华州州立大学和艾姆斯实验室工作，以推进这些领域的材料科学的重大利益的行业。 学生将学习高温化学，分析，衍射和电子结构理论的方法。 这项关于固体结构和键合的研究的基本结果正在被纳入爱荷华州州立大学提供的课程中。*

This project aims to use both experiment and theory to systematically search for new intermetallic compounds with potentially interesting physical and chemical properties. Since subtle changes of composition can lead to drastic effects on structural and physical properties in intermetallics, theoretical calculations of electronic structure will play a significant role in a complete and systematic study of these phases. The synthesis and detailed characterization of new multinary compounds will involve (i) an electropositive alkali, alkaline earth, or rare earth metal; (ii) a transition metal; and (iii) a group 13 element (aluminum, gallium, indium), or magnesium or manganese. The group 13 elements are selected because their position in the periodic table of elements is at the border between metals and nonmetals. These combinations of elements are anticipated to create beautifully complex structures involving interconnected and interpenetrating clusters of atoms that will allow a thorough investigation of the relationships among composition, structure, properties, and chemical bonding.%%%Materials with possible applications as thermoelectrics, or as strong, high temperature conductors that are anticipated to be environmentally benign will be synthesized and characterized. The project will involve students of chemistry, physics and materials science working through Iowa State University and the Ames Laboratory to advance these areas of materials science of significant interest to industry. Students will learn methods in high temperature chemistry, analysis, diffraction and electronic structure theory. Fundamental results from this research regarding the structure and bonding of solids are being incorporated into courses being offered at Iowa State University.***