Confusion with pair_coeff...

Dear LAMMPS users,

I am used to the regular pair_coeff representation where first we have the pair coefficients in the following format:

 1 coeff1 coeff2 ...
  N coeff1 coeff2 ...              (N = # of atom types)

which is clear because you know which atom types are in question.

However, I came across an example in the peptide example folder, where there is pair coefficients listed without the coeff1 coeff2 notation. This is extremely confusing. How do I know what is going on and what the values actually represent?

This is an example from the pair coefficient part of the data file:
Pair Coeffs

1 0.110000 3.563595 0.110000 3.563595
2 0.080000 3.670503 0.010000 3.385415

Thank you for any input.


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