Hello Everyone,

I have to switch to LAMMPS for simulation due to its flexibility. But while using msi2lmp tool, I found that some parameters were missing, msi2lmp tool failed to bond coefficient data between carbon and nitrogen and more. Any Idea about this missing parameters. I have observed

C:\one\msdata\compass>“C:\Program Files\LAMMPS 64-bit 19Mar2020-MPI\bin\msi2lmp.exe” C:\one\msdata\pcff\OCOOHTENXLINKNPTMS -p 2 -c 2 -frc “C:\Program Files\LAMMPS 64-bit 19Mar2020-MPI\frc_files\pcff.frc” -i

Running msi2lmp v3.9.9 / 05 Nov 2018

Forcefield: Class II

Forcefield file name: C:\Program Files\LAMMPS 64-bit 19Mar2020-MPI\frc_files\pcff.frc

Output is recentered around geometrical center

Output contains style flag hints

System translated by: 0 0 0

Reading car file: C:\one\msdata\pcff\OCOOHTENXLINKNPTMS.car

There are 20833 atoms in 1 molecules in this file

The total charge in the system is -0.318.

7441 of 20833 atoms with nonzero image flags

Reading mdf file: C:\one\msdata\pcff\OCOOHTENXLINKNPTMS.mdf

Building internal coordinate lists

Number of bonds, types = 22936 20

Number of angles, types = 41438 40

Number of dihedrals, types = 63120 52

Number of out-of-planes, types = 7372 9

Number of Angle Angle Terms, types = 12036 23

Reading forcefield file

Using higher version of parameters for #equivalence Na Na Na Na Na Na version 2.10

Using higher version of parameters for #nonbond c= version 2.10

Using higher version of parameters for #nonbond ho2 version 2.10

Using higher version of parameters for #nonbond n= version 3.10

Using higher version of parameters for #nonbond nz version 2.10

Using higher version of parameters for #nonbond o_1 version 2.10

Using higher version of parameters for #nonbond s’ version 2.10

Using higher version of parameters for #nonbond si version 2.20

Using higher version of parameters for #quartic_bond c c version 2.10

Using higher version of parameters for #quartic_bond c h version 2.10

Using higher version of parameters for #quartic_bond c o_2 version 2.20

Using higher version of parameters for #quartic_bond c= c=1 version 3.10

Using higher version of parameters for #quartic_bond c_1 o_1 version 2.10

Using higher version of parameters for #quartic_bond cp cp version 2.10

Using higher version of parameters for #quartic_bond cp cp version 2.10

Using higher version of parameters for #quartic_bond cp h version 2.10

Using higher version of parameters for #torsion_3 c c c c version 2.10

Using higher version of parameters for #torsion_3 c c c h version 2.10

Using higher version of parameters for #torsion_3 h c c h version 2.10

Using higher version of parameters for #torsion_3 h c cp cp version 2.00

Using higher version of parameters for #wilson_out_of_plane c cp cp cp version 2.00

Using higher version of parameters for #wilson_out_of_plane cp cp cp h version 3.10

Using higher version of parameters for #middle_bond-torsion_3 o_1 c_1 o_2 c version 2.10

Using higher version of parameters for #bond-bond_1_3 cp cp cp cp version 2.10

Item #atom_types has 133 entries

Item #equivalence has 133 entries

Item #nonbond has 87 entries

Item #quartic_bond has 119 entries

Item #quartic_angle has 303 entries

Item #bond-bond has 245 entries

Item #bond-angle has 234 entries

Item #torsion_3 has 488 entries

Item #angle-torsion_3 has 303 entries

Item #angle-angle-torsion_1 has 328 entries

Item #end_bond-torsion_3 has 291 entries

Item #middle_bond-torsion_3 has 350 entries

Item #bond-bond_1_3 has 63 entries

Item #wilson_out_of_plane has 69 entries

Item #angle-angle has 270 entries

Get force field parameters for this system

Trying Atom Equivalences if needed

Unable to find bond data for c2 nb

Unable to find bondbond data for cp c2 cp

Unable to find bondangle data for cp c2 cp

Unable to find bondbond data for cp oc c2

Unable to find bondangle data for cp oc c2

Unable to find angle data for c1 c2 nb

Unable to find bondbond data for c1 c2 nb

Unable to find bondangle data for c1 c2 nb

Unable to find angle data for hc c2 nb

Unable to find bondbond data for hc c2 nb

…

I have no idea about how atom equivalencies are performed. Currently, I am looking at how to do it. I have seen authors have use PCFF for crosslinked structure. Any idea about how to do it or update regarding another tool that I can use.

Thanks,

Ankit