Temperature-induced electride transition in dense lithium

As a prototypical light metal, lithium shows various and intriguing behaviors including electride character under high pressure. It has pronounced melting line depression from 40 to 60 GPa, yet precise detailed understanding of this minimum remains elusive. Here, using computations that include metadynamics, crystal structure searching, molecular dynamics with machine learned potentials, we demonstrate temperature-induced (pocketlike tubelike) transition accompanied by complex structural phase transitions in dense premelting lithium. The possible rearrangement nearest neighbors three-coordinated net dimers the collective atomic motion affected electronic demonstrates combined influence temperature on high-pressure metals.