[lammps-users] pair coeffs error with setting up SAM-Au simulation

Hi,

I was trying to build a SAM-Au simulation, my input file contains

units real
boundary f p p
atom_style molecular

pair_style lj/cut 2.5
bond_style harmonic
angle_style harmonic

read_data SAM-Au.d

pair_style eam
pair_coeff 1 1 Au_u3.eam
pair_style morse 2.5
pair_coeff 1 2 0.1378 0.01477 2.56 2.5

and my data file head is like

80785 atoms
      9515 bonds
      7612 angles

         4 atom types
         3 bond types
         4 angle types

       -30 100 xlo xhi
      -100 100 ylo yhi
      -100 100 zlo zhi

Masses

  1 196.97
  2 32.065
  3 14.0266
  4 15.03455

Pair Coeffs

  1 2.935 0.039
  2 4.250 1.6629
  3 3.905 0.495
  4 3.905 0.7325

Bond Coeffs

  1 132600 1.82
  2 132600 1.53
  3 132600 1.53

Angle Coeffs

  1 63.0 100.0
  2 62.5 114.4
  3 63.0 109.5
  4 63.0 109.5

However I keep getting the ERROR: All pair coeffs are not set.

According to log.lammps this error comes after run command is called,
and I could not figure out which pair coeffs I've missed

My SAM-Au contains four atoms(and pesudo atoms) Au, S, CH2, CH3

Thanks!

Xiaoyin Ji

Hi,

[...]

pair_style eam
pair_coeff 1 1 Au_u3.eam
pair_style morse 2.5
pair_coeff 1 2 0.1378 0.01477 2.56 2.5

this does not work. you have to use pair_style hybrid
to use two different pair styles in the same input.
the second will override the first, hence the error.

cheers,
    axel.