pair coeff

Dear LAMMPS users,

I am trying to find thermal conductivity of combination of bio-molecules/crystals (mainly hydroxyapatite and collagen).

I have used topo tools to get lammps input data file from PDB file. Although I have got all the co-ordinates, angles, dihedrals, impropers etc., I am particularly finding difficulty in giving pair coefficients.
As there are 17 atom types, 1 bond type, 21 angle types, 20 dihedral types, 3 improper types, I am confused how to give pair coefficients!!
I am using LJ potential for starting purpose. Later I will go for other potentials for getting closer values to literature. If anybody have got lammps input script (apart from manual ) for predicting thermal conductivity of bio-molecules /crystals , kindly pass on as it will be much more helpful .
I am attaching the lammps input data file



molecule.txt (241 KB)