About Pair style hybrid

Dear all, I am setting up a simulation of a polymer and TIP3P water using the hybrid overlay pair style but keep getting the error: Pair coeff for hybrid has invalid style. I have checked documentation and defined the substyles in the pairstyle command but the error persists. I have posted the erring sections of the input file and the two data files. Please help.

pair_style hybrid/overlay lj/charmm/coul/long 8.0 10.0 lj/cut/coul/long 10.0
read_data datafile1 extra/atom/types 2 extra/bond/types 1 extra/angle/types 1 extra/dihedral/types 0 extra/improper/types 0
read_data datafile2 add append offset 7 8 13 13 1 group water shift 0 0 0
displace_atoms water move 0 0 150 units box

Data file 1:

Pair Coeffs

1 lj/charmm/coul/long 7.0000E-002 3.5500000840408314 3.5000000035901847E-002 3.5500000840408314
2 lj/charmm/coul/long 7.00000E-002 3.5500000840408314 3.5000000035901847E-002 3.5500000840408314
3 lj/charmm/coul/long 7.00000E-002 3.5500000840408314 3.5000000035901847E-002 3.5500000840408314
4 lj/charmm/coul/long 0.24999998789 3.5500000840408314 0.12499999995788810 3.5500000840408314
5 lj/charmm/coul/long 6.599999998253E-002 3.5000001306733628 3.3000000090627910E-002 3.5000001306733628
6 lj/charmm/coul/long 2.999999997399E-002 2.4200001437387519 1.5000000006869867E-002 2.4200001437387519
7 lj/charmm/coul/long 2.999999997399E-002 2.5000000682689802 1.5000000006869867E-002 2.5000000682689802

Data file2 (water):

Pair Coeffs
1 1 lj/cut/coul/long 0.000000 0.000000 10.000000
1 2 lj/cut/coul/long 0.000000 0.000000 10.000000
2 2 lj/cut/coul/long 0.102000 3.150700 10.000000

Dear all, I am setting up a simulation of a polymer and TIP3P water using the hybrid overlay pair style but keep getting the error: Pair coeff for hybrid has invalid style. I have checked documentation and defined the substyles in the pairstyle command but the error persists. I have posted the erring sections of the input file and the two data files. Please help.

you cannot do what you are doing, the PairCoeff section requires
mixing to be available, but you cannot mix between different pair
styles. i would argue, that there is not enough of a difference
between lj//cut/coul/long and lj/charmm/coul/long, that you should
just choose one of the two. since you are apparently mixing and
matching different force fields (which is a questionably and risky
practice in the first place), the difference between a straight cutoff
lj/cut and the smooth cutoff in lj/charmm should not be relevant.
without hybrid, there should be not problems.

the alternative would be to use PairIJCoeff instead of PairCoeff, or
directly pair_coeff in the input files. both are compatible with
hybrid, but they also require you to explicitly compute the mixed
terms, since there cannot be automated mixing between different
substyles, anyway.

axel.