Hi,
I’m trying to perform a md/gcmc simulation using morse potential instead LJ.
My system is a box of methane ak 180K and 2.5 bar
I defined
pair_style hybrid/overlay coul/cut/omp 16.5 morse/omp 16.5
partial charge on atoms
atomic charges
set type 1 charge 0.14368 #C
set type 2 charge -0.03592 #H
and pair_coeff as documented in manual (lammps7Aug-2019)
pair coeff coulomb
pair_coeff * * coul/cut/omp
pair coeff MORSE
pair_coeff 1 1 morse/omp 0.017700 1.7521 3.5284 # C
pair_coeff 2 2 morse/omp 0.003345 1.2278 2.2301 # H
pair_coeff 1 2 morse/omp 0.007695 1.4900 2.8793 # C-H mixing arithmetic rule
As results I noticed that the E_coul is nan or inf for a low density and E_vdwl is much great
How I could fix it?
or this is a bug?
regards
Alberto
results
Step Temp v_TEMPCH4s Volume Atoms Density v_molec_CH4 v_rho_mol_L v_P1 v_Temp E_coul E_vdwl
0 270.0444 1350.222 35937 10 0.0014825988 2 0.092413883 2.5 180 3.6393876e-07 -8.5286732e-14
5000 26.483367 132.41683 35937 30 0.0044477963 6 0.27724165 2.5 180 -0.33923563 -5.5761078e-08
10000 36.320768 181.60384 35937 30 0.0044477963 6 0.27724165 2.5 180 0.10758413 -5.9681681e-08
15000 19.293819 96.469094 35937 25 0.0037064969 5 0.23103471 2.5 180 -0.057303482 -7.391762e-12
20000 30.691982 153.45991 35937 5 0.00074129938 1 0.046206942 2.5 180 0 0
25000 46.587045 232.93522 35937 20 0.0029651975 4 0.18482777 2.5 180 0.076663171 -5.8667774e-13
30000 40.336166 201.68083 35937 15 0.0022238981 3 0.13862083 2.5 180 -0.15820937 -2.5952994e-08
35000 51.786429 258.93215 35937 20 0.0029651975 4 0.18482777 2.5 180 -0.10138811 -2.5763632e-06
40000 43.670983 218.35492 35937 20 0.0029651975 4 0.18482777 2.5 180 -0.077061111 -3.492686e-14
45000 42.841612 214.20806 35937 35 0.0051890956 7 0.32344859 2.5 180 -0.28848025 -0.00066032115
50000 66.535944 332.67972 35937 15 0.0022238981 3 0.13862083 2.5 180 0.0011888624 -3.449481e-13
55000 30.912156 154.56078 35937 35 0.0051890956 7 0.32344859 2.5 180 0.2877785 -8.5057088e-07
60000 32.557839 162.78919 35937 15 0.0022238981 3 0.13862083 2.5 180 -0.18555578 -1.1987077e-12
65000 35.861469 179.30734 35937 20 0.0029651975 4 0.18482777 2.5 180 -0.36761343 -1.9408775e-07
70000 23.485044 117.42522 35937 20 0.0029651975 4 0.18482777 2.5 180 -6.8786212e-06 -3.2978556e-06
75000 35.095379 175.47689 35937 10 0.0014825988 2 0.092413883 2.5 180 0.079558559 -6.1023265e-17
80000 15.599731 77.998655 35937 10 0.0014825988 2 0.092413883 2.5 180 0 0
85000 35.508654 177.54327 35937 20 0.0029651975 4 0.18482777 2.5 180 -0.36600665 -0.00093791313
90000 40.000156 200.00078 35937 10 0.0014825988 2 0.092413883 2.5 180 0.17931591 -9.6378068e-16
95000 39.714319 198.5716 35937 20 0.0029651975 4 0.18482777 2.5 180 -0.18603875 -0.0011543274
100000 84.240941 421.20471 35937 5 0.00074129938 1 0.046206942 2.5 180 0 0
105000 16.878858 84.394288 35937 30 0.0044477963 6 0.27724165 2.5 180 0.13071772 -0.00039949925
110000 39.24708 196.2354 35937 30 0.0044477963 6 0.27724165 2.5 180 -0.23382248 -2.9007375e-07
115000 36.985683 192.66622 35937 20 0.0028720471 4 0.18482777 2.5 180 inf 166.69034
120000 38.496148 201.23789 35937 20 0.0028254719 4 0.18482777 2.5 180 inf 165.12337
125000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 -nan 322.79944
130000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 inf 322.79941
135000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 -nan 322.79944
140000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 inf 322.79941
145000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 -3.3549841e+10 156.98941
150000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 -3.3549841e+10 156.98941
155000 39.142228 195.71114 35937 20 0.0022238981 4 0.18482777 2.5 180 -nan 322.79941
160000 37.347727 195.71114 35937 20 0.0022704733 4 0.18482777 2.5 180 -3.3549841e+10 156.98941
165000 39.142228 195.71114 35937 20 0.0022238981 4 0.18482777 2.5 180 -inf 322.79944
170000 43.529559 217.6478 35937 20 0.0021307477 4 0.18482777 2.5 180 -nan 166.71704
175000 43.529559 217.6478 35937 20 0.0021307477 4 0.18482777 2.5 180 inf 166.71704
180000 43.529559 217.6478 35937 20 0.0021307477 4 0.18482777 2.5 180 -nan 166.71704
185000 43.529559 217.6478 35937 20 0.0021307477 4 0.18482777 2.5 180 inf 166.71704
190000 43.529559 217.6478 35937 20 0.0021307477 4 0.18482777 2.5 180 -nan 166.71704
195000 43.529559 217.6478 35937 20 0.0021307477 4 0.18482777 2.5 180 -nan 166.71704