# SPC/E water vapor units metal atom_style full boundary p p p region Box block 0 100.0 0 100.0 0 100.0 units box create_box 2 Box bond/types 1 angle/types 1 extra/bond/per/atom 2 extra/angle/per/atom 1 extra/special/per/atom 2 # ======================== create vapor ====================== molecule H2O molecule.H2O create_atoms 0 random 1 3923 Box mol H2O 9382 units box group Vapor type 1 2 # ================== interaction potentials =================== mass 1 15.9994 mass 2 1.00794 pair_style lj/cut/coul/long 14.0 14.0 kspace_style pppm 1.0e-5 pair_coeff 1 1 6.734e-3 3.166 # O pair_coeff * 2 0.0 0.0 # H pair_modify shift yes bond_style harmonic angle_style harmonic dihedral_style none improper_style none bond_coeff 1 1000.0 1.000 angle_coeff 1 100.0 109.47 special_bonds lj/coul 0.0 0.0 0.5 neighbor 2.0 bin neigh_modify every 1 delay 0 check yes # ========================= run ================================ timestep 0.001 compute T_vapor Vapor temp compute_modify T_vapor dynamic yes # ---- NVE and check the SHAKE and intramolecular energy ---- thermo 1000 thermo_style custom step c_T_vapor pe ke emol ecoul etotal press density atoms thermo_modify flush yes dump 2 Vapor custom 1000 vapor_nve.dat id mol type x y z vx vy vz fx fy fz dump_modify 2 sort id fix 1 Vapor shake 0.0001 20 0 b 1 a 1 mol H2O fix 3 Vapor nve run 10000 unfix 3 undump 2 # ---- gcmc and check the SHAKE --- fix 2 Vapor gcmc 10 10 20 0 9248 400.0 0 1.0 mol H2O shake 1 pressure 1.0 tfac_insert 2 full_energy dump 2 Vapor custom 100 vapor.dat id mol type x y z vx vy vz fx fy fz dump_modify 2 sort id thermo 100 thermo_style custom step c_T_vapor pe ke emol ecoul press density atoms f_2[1] f_2[2] f_2[3] f_2[4] f_2[5] f_2[6] f_2[7] f_2[8] thermo_modify flush yes run 30000