5 / 2025-02-07 23:22:41

Research on Defect Behavior of Electrides: Taking Dense FCC-Li and hP4-Na as Examples

Electrides,Crystal defects,ISQ,First principles calculations

Electrides are an emerging class of materials with highly-localized electrons in the interstices of a crystal that behave as anions. The presence of these unusual anionic interstitial quasi-atom (ISQ) electrons leads to wide promising applications for this new category of materials. Materials in actual service environment (such as high temperature, high pressure, irradiation, etc.) usually produce various crystal defects (such as lattice distortion, impurity atoms, stacking faults, etc.), and defects are also an important engineering means to regulate material properties. Therefore, in-depth and systematic theoretical research on defect behavior in electrides is of great significance. The study of dense FCC-Li and hP4-Na show that the presence of ISQ has a significant effect on the preferred occupancy, chemical valence state, and migration path of point defects in these materials. In addition, the changes in local crystal and electronic structure caused by defects can effectively regulate the electronic bandgap of hP4-Na. This report will introduce the recent advance in the interaction behavior and pressure response characteristics between anionic ISQs and crystal point defects in electrides.