Dear Sir or Madam,
I have been trying to use buck/coul potential to find the bond length of metal oxide. The parameters are found in literature. My input is following and data file is attached:
---------- Initialize Simulation ---------------------
clear
units metal
dimension 3
boundary p p p
atom_style charge
---------- Create Atoms ---------------------
read_data data_new_RS.MO
mass 1 24.304 #Mg
mass 2 58.933 #Co
mass 3 63.546 #Cu
mass 4 58.693 #Ni
mass 5 65.38 #Zn
mass 6 16.0 #O
---------- Define Interatomic Potential ---------------------
pair_style buck/coul/long 10.0 10.0
pair_coeff * * 0.0 0.1 0.0
pair_coeff 1 6 821.6 0.3242 0.0
pair_coeff 2 6 696.3 0.3362 0.0
pair_coeff 3 6 3860.6 0.2427 0.0
pair_coeff 4 6 683.5 0.3332 0.0
pair_coeff 5 6 499.6 0.3595 0.0
pair_coeff 6 6 22764.0 0.1490 43.0
neigh_modify every 1 delay 0 check yes
kspace_style ewald 1.e-6
---------- Run Minimization ---------------------
reset_timestep 0
fix 1 all box/relax aniso 0.0 vmax 0.001
thermo 100
thermo_style custom step pe lx ly lz press pxx pyy pzz
min_style cg
minimize 1e-10 1e-10 5000 10000
The results are
Step PotEng Lx Ly Lz Press Pxx Pyy Pzz c_
0 -20552.037 20.7 20.7 20.7 7907.1889 7907.1889 7907.1889 7907.1889
100 -20562.403 20.723425 20.723557 20.73678 786.91633 1136.4082 1140.623 83.717806
200 -20564.346 20.728921 20.72917 20.737892 401.429 639.02306 650.0531 -84.789163
300 -20565.977 20.734838 20.735478 20.739051 159.0794 274.43534 281.81439 -79.011541
376 -20568.192 20.750291 20.751315 20.747824 94.9827 -17.705675 174.78765 127.86612
Loop time of 14.1734 on 4 procs for 376 steps with 1000 atoms
It can be seen that the pressure is really high after minimization is converged. I have no idea why this happened so would you please help check this and let me know where I got wrong? Thank you very much!
Best,
Siming
data_new_RS.MO (46 KB)