Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); imaginary modes detected; min freq = -2.72 THz
Cell + Ionic relaxation with Orb v3; 0.03 eV/Å threshold; final energy = -63.0155 eV; energy change = -0.0977 eV; symmetry: P4mm → P4mm
