Enter an atomic species: Xe Enter a cubic lattice type: fcc Enter a model name: LJ_Shifted_Bernardes_1958LowCutoff_Xe__MO_648694198005_004 Enter a lattice constant (m): 6.164724573493004e-10 Writing phonon.eq.pckl Writing phonon.0x-.pckl Writing phonon.0x+.pckl Writing phonon.0y-.pckl Writing phonon.0y+.pckl Writing phonon.0z-.pckl Writing phonon.0z+.pckl WARNING, 3 imaginary frequencies at q = ( 0.00, 0.00, 0.00) ; (omega_q = 1.760e-09*i) WARNING, 3 imaginary frequencies at q = ( 0.00, 0.00, 0.00) ; (omega_q = 1.760e-09*i)