echo both units real atom_style atomic variable L equal 6 variable w equal 2 lattice fcc 5.405 origin 0.25 0.25 0.25 region BOX block -$L $L -$L $L -$w $w boundary f f p create_box 1 BOX create_atoms 1 region BOX mass 1 39.95 pair_style lj/cut 13.5 pair_coeff 1 1 .238 3.405 13.5 group internal region BOX fix AtC internal atc hardy fix_modify AtC kernel quartic_sphere 5.0 fix_modify AtC mesh read gaussianIC2d_tet.mesh fix_modify AtC fields add mass_density fix_modify AtC output kernel2d_tetFE 1 full_text binary thermo_style custom step cpu temp timestep 0.0 thermo 1 run 2