Fig. 1. The crystal structure of Ti₃B₄: (a) The unit cell; (b) the supercell. The blue balls in the figure denote the Ti atoms, and the green balls refer to the B atoms.

Fig. 2. The stress-strain relationship of Ti₃B₄ under uniaxial compressions.

Fig. 3. The structural and ELF at various strains under a-axis uniaxial compression: (a) ε = 0.00; (b) ε = 0.10; (c) ε = 0.15; (d) ε = 0.24; (e) ε = 0.242.

Fig. 4. Variation of bond lengths as a function of a-axis uniaxial compressive strain.

Fig. 5. The ELF at critical strains of (100) crystal plane in Ti₃B₄ structure under a-axis uniaxial compression: (a) ε = 0.24; (b) ε = 0.242.

Fig. 6. The structural and ELF at various strains under b-axis uniaxial compression: (a) ε = 0.10; (b) ε = 0.14; (c) ε = 0.26; (d) ε = 0.268.

Fig. 7. Variation of bond lengths as a function of b-axis uniaxial compressive strain.

Fig. 8. The ELF at critical strains of (100) crystal plane in Ti₃B₄ structure under b-axis uniaxial compression: (a) ε = 0.14; (b) ε = 0.20; (c) ε = 0.26; (d) ε = 0.268.

Fig. 9. The structural and ELF at various strains under c-axis uniaxial compression: (a) ε = 0.10; (b) ε = 0.13; (c) ε = 0.18; (d) ε = 0.20; (e) ε = 0.26.

Fig. 10. Variation of bond lengths in Ti₃B₄ as a function of c-axis uniaxial compressive strain.

Fig. 11. TDOS and PDOS for undeformed Ti₃B₄.

Fig. 12. TDOS and PDOS for Ti₃B₄ at critical strains under uniaxial compressions: (a) ε = 0.242 (a-axis); (b) ε = 0.268 (b-axis); (c) ε = 0.19 (c-axis).