Solid State Chemistry of Rare-Earth and Intermetallic Compounds

金属构成了元素周期表中的绝大多数元素。 一般来说，仍然很难预测金属如何与其他金属反应，以及它们形成的化合物的组成，结构和性质。 然而，这些“金属间化合物”对推动人类进步非常重要，从几千年前我们的祖先制造的青铜工具开始，到我们现在认为理所当然的先进材料，如计算机和电子设备。 在我们的研究中，我们寻求发现新的金属间化合物，发展其化学键的基本理解，将其原子排列与其物理性质联系起来，并确定有希望的候选材料应用。 我们研究的一组重要的金属是“稀土”元素，它们用于许多能源，通信和国防应用中的催化剂，磁铁和磷光体。 由于全球稀土金属的生产绝大多数集中在中国（>97%），减少供应脆弱性的战略是投资研发，以寻找稀土的新技术应用，使加拿大境内的稀土提取更具经济可行性。 我们将研究稀土金属，过渡金属和15族非金属的组合，目标是可能导致新超导体（可以允许无电阻电流）和热电材料（可以从废热中产生电力）的晶体结构。 实验方法涉及在非常高的温度（通常接近1000 °C！）下使金属反应，通过X射线衍射技术解开复杂的晶体结构，测量电和磁特性，并进行量子计算。 由于学生成为固态化学，物理学和材料科学的不同领域的专家，他们拥有的多功能性是在先进材料研究领域的职业生涯至关重要。

Metals constitute the vast majority of elements in the periodic table. In general, it is still difficult to predict how metals will react with other metals, and what will be the compositions, structures, and properties of the compounds they form. Yet, these "intermetallic compounds" have been enormously important for advancing human progress, traversing great arcs in history starting from the bronze tools manufactured by our forebears millenia ago, to the advanced materials we now take for granted such as computers and electronic devices. In our research, we seek to discover new intermetallics, to develop a fundamental understanding of their chemical bonding, to relate their atomic arrangements to their physical properties, and to identify promising candidates for materials applications. An important group of metals we study are the "rare-earth" elements, which are used for catalysts, magnets, and phosphors in many energy, communications, and defense applications. Because the global production of rare-earth metals is concentrated overwhelmingly (>97%) in China, a strategy to reduce supply vulnerability is to invest in R&D to find new technological applications of rare-earths so that their extraction within Canada becomes more economically viable. We will examine combinations of rare-earth metals, transition metals, and group 15 metalloids, targeting crystal structures that are likely to lead to new superconductors (which can allow resistanceless flow of electricity) and thermoelectric materials (which can generate electrical power from waste heat). The experimental approach involves reacting metals at very high temperatures (often close to 1000 °C!), unravelling the complex crystal structures through X-ray diffraction techniques, measuring electrical and magnetic properties, and performing quantum calculations. Because students become experts in diverse areas of solid state chemistry, physics, and materials science, they possess the versatility that is critical for careers in the advanced materials research sector.