Superconducting, structural, and magnetic properties of lithium and lithium-rich compounds

Lithium is generally considered to be a simple metal, given its simple electronic structure with one valence electron. It is considered to follow a nearly free electron model and have a nearly spherical Fermi surface. However, away from ambient conditions, the behavior of lithium become much less simple. Under high pressures, lithium undergoes a series of symmetry-breaking phase transitions, even a metal to insulator transition; at low temperatures, lithium also undergoes a temperature-driven martensitic transformation. In this work, these deviations from simple models in lithium are investigated, both at ambient pressure and under high pressures, from the relative high temperature phenomenon of melting to low temperature measurements of superconductivity.