Fig. 7. The diffusion barrier profiles of (a) Li, Na (b) Mg on the Ti₃N₂ monolayer, (d) Li, Na on the Ti₃N₂F₂ monolayer, (e) Li, Na, Mg on the Ti₃N₂O₂ monolayer. (c) Labeling of the high symmetry points appearing in the diffusion paths. The site “a” and “a′” are on top of Ti(2) atoms for bare Ti₃N₂ and occupied by X for Ti₃N₂X₂. The site “b” and “b′” are on top of N atoms. The site “c” is on top of Ti(1) atom.