Cannot get data file by combining Packmol with Moltemplate

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First of all, please read the forum guidelines and do some research before posting questions.

As @Germain suggested, this issue is really a missing parameter in the OPLS-AA force distributed with Moltemplate, so please raise an issue on GitHub. Also, please read this discussion about the versioning of the OPLS-AA force field.

The error explained: the bond coefficient for the hexafluorophosphate ion is not defined in the oplsaa.lt file. You can fix this by adding the relevant command to the definition of LiPF6.lt:

# No need to define the absolute path if you configured Moltemplate correctly ;)
import oplsaa.lt 

LiPF6 inherits OPLSAA {

 # atomID molID atomType charge coordX coordY coordZ
 write("Data Atoms") {
  $atom:P  $mol @atom:726 0.00 -1.051 1.315 -0.000
  $atom:F1 $mol @atom:727 0.00 -0.314 2.271 1.222
  $atom:F2 $mol @atom:727 0.00 -1.788 0.359 -1.222
  $atom:F3 $mol @atom:727 0.00 0.323 0.283 -0.021
  $atom:F4 $mol @atom:727 0.00 -0.328 2.301 -1.207
  $atom:F5 $mol @atom:727 0.00 -1.773 0.328 1.207
  $atom:F6 $mol @atom:727 0.00 -2.424 2.346 0.021
  $atom:Li $mol @atom:879 0.00 3.044 0.685 -1.952
 }

# A list of the bonds in the molecule:
# BondID AtomID1 AtomID2
 write("Data Bond List") {
  $bond:PF1 $atom:P $atom:F1
  $bond:PF2 $atom:P $atom:F2
  $bond:PF3 $atom:P $atom:F3
  $bond:PF4 $atom:P $atom:F4
  $bond:PF5 $atom:P $atom:F5
  $bond:PF6 $atom:P $atom:F6
 }

 # Add the missing coefficients and types:
 write_once("In Settings") {
   bond_coeff  @bond:064_001       370.46  1.606
   angle_coeff @angle:001_064_001  139.22 90.0
 }
 write_once("Data Bonds By Type") {
   @bond:064_001 @atom:*_b001*_a*_d*_i* @atom:*_b064*_a*_d*_i*
 }
 write_once("Data Angles By Type") {
   @angle:001_064_001 @atom:*_b*_a001*_d*_i* @atom:*_b*_a064*_d*_i* @atom:*_b*_a001*_d*_i*
 }
}

I have taken the bond coefficient from this repository, but you would do to the community a better favour if you could identify the missing coefficient in the original OPLS-AA version. Please note that the OPLS-AA version in Moltemplate has been converted from:

The parameters supplied with Tinker are from “OPLS All-Atom Parameters for Organic Molecules, Ions, Peptides & Nucleic Acids, July 2008” as provided by W. L. Jorgensen, Yale University during June 2009. These parameters are taken from those distributed with BOSS Version 4.8.

PS I haven’t checked this choice of parameters, so please be very careful and compare this force field with some references.

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