Pair hybrid sub-style is not used

LAMMPS LAMMPS General Discussion
1

Hello,

I am trying to save a data file using write_data command. I have six types of atoms. I used the hybrid potential and defined all the interactions for all six types of atoms. My goal is to have:

6 with 1 to 5: gauss/cut
6 with 6: no interaction
everything else: eam/alloy

However, I am receiving an error:

pair_style hybrid gauss/cut 2.0 eam/alloy
pair_coeff * * eam/alloy Fe-Ni-Cr-Co-Cu.eam.alloy Fe Ni Cr Co Cu NULL
pair_coeff 6 * gauss/cut 100 0.5 1.0
pair_coeff 6 6 none

write_data groove_configuration.dat

System init for write_data …
ERROR: Pair hybrid sub-style is not used (…/pair_hybrid.cpp:537)
Last command: write_data groove_configuration.dat

Could anyone please provide some clarification for this?

2

Here is the problem. The documentation for pair_coeff says:

For numeric values only, a wildcard asterisk can be used in place of or in conjunction with the I,J arguments to set the coefficients for multiple pairs of atom types. This takes the form “*” or “*n” or “n*” or “m*n”. If N is the number of atom types, then an asterisk with no numeric values means all types from 1 to N. A leading asterisk means all types from 1 to n (inclusive). A trailing asterisk means all types from n to N (inclusive). A middle asterisk means all types from m to n (inclusive). For the asterisk syntax, only type pairs with I <= J are considered; if asterisks imply type pairs where J < I, they are ignored. Again internally, LAMMPS will set the coefficients for the symmetric J,I interactions to the same values as the I <= J interactions.

So “pair_coeff 6 *” is equivalent to “pair_coeff 6 6” and that one is wiped out with the following pair_coeff command.

4

Thank you very much, I got it now.