Department of Physics and Astronomy Colloquium

Professor Laura Lewis from Northeastern University.

It is almost impossible to avoid headlines concerning critical minerals and their supply, sourcing and geopolitical impact that touches every continent of our planet. While considered to be critical, the rare earth elements, also known as the Lanthanides, are a family of medium-weight elements distinguished by lower-energy 4f electrons that are located within, and thus shielded by, electrons resident in higher-energy 5d shells. This unique electronic character confers important properties to materials containing rare earths, with applications that include strong magnets necessary for energy generation and transformation. However, the electronic structure of the rare earth elements also furnishes considerable challenges in their sourcing, separation and purification. This presentation introduces the rare earth elements, their role in strong magnets, and how the global research community is addressing their use and conservation.