Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); imaginary modes detected; min freq = -0.61 THz
Cell + Ionic relaxation with Orb v3; 0.03 eV/Å threshold; final energy = -136.7751 eV; energy change = -4.1985 eV; symmetry: I4/mmm → I4/mmm
