Predicted Stable Structures of the Li-Ag System at High Pressures.

In this letter, we have performed extensive swarm-intelligence structure searching simulations on the Li-Ag system at high pressures. As a result, Li4Ag is predicted to become stable at high pressures. Moreover, we have also identified several pressured-stabilized structures for the Li-Ag system. The further electronic density of states and electron localization function calculations reveal the metallic feature of predicted structures. Crystal orbital Hamilton population (COHP) calculations indicate the strong interaction between Li atoms, leading to the formation of Li-ring configurations in Li-rich Li-Ag structures. Our current results highlight the role of pressure in determining the stability for unexpected stoichiometry in the Li-Ag system.