Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); no imaginary modes; min freq = -0.08 THz
Cell + Ionic relaxation with Orb v3; 0.03 eV/Å threshold; final energy = -152.6010 eV; energy change = -5.4313 eV; symmetry: R3m → P1
