angle_style hybrid class2 harmonic: how to write bondbond coeff and bondangle coeff in the input script

Hi

I am using angle_style hybrid class2 harmonic. I am trying to include bondbond coeff and bondangle coeff in the input script. I generated input script as below. Since the restart file does not include those angle coefficients, I would like to include angle coeff, bondbond coeff, and bondangle coeff in the input script.

Below is my input file.

angle_coeff 1 class2 110.6204 51.3137 -6.7198 -2.6003

angle_coeff 2 class2 111.9100 60.7147 -13.3366 -13.0785

angle_coeff 3 class2 110.7700 41.4530 -10.6040 5.1290

angle_coeff 4 class2 107.6600 39.6410 -12.9210 -2.4318

angle_coeff 5 class2 112.4436 47.2337 -10.6612 -10.2062

angle_coeff 6 class2 110.9538 50.8652 -4.4522 -10.0298

angle_coeff 7 class2 107.0671 45.2520 -7.5558 -9.5120

angle_coeff 8 harmonic 55.0000 104.5200

bondbond_coeff 1 class2 12.4260 1.4570 1.1010

bondbond_coeff 2 class2 4.6217 1.5300 1.4570

bondbond_coeff 3 class2 3.3872 1.5300 1.1010

bondbond_coeff 4 class2 5.3316 1.1010 1.1010

bondbond_coeff 5 class2 -2.1113 1.4570 1.4570

bondbond_coeff 6 class2 -6.4168 1.4570 1.0060

bondbond_coeff 7 class2 -1.8749 1.0060 1.0060

bondbond_coeff 8 skip

bondangle_coeff 1 class2 42.4332 13.4582 1.4570 1.1010

bondangle_coeff 2 class2 6.0876 16.5702 1.5300 1.4570

bondangle_coeff 3 class2 20.7540 11.4210 1.5300 1.1010

bondangle_coeff 4 class2 18.1030 18.1030 1.1010 1.1010

bondangle_coeff 5 class2 -7.2229 -7.2229 1.4570 1.4570

bondangle_coeff 6 class2 31.8096 20.5799 1.4570 1.0060

bondangle_coeff 7 class2 28.0322 28.0322 1.0060 1.0060

bondangle_coeff 8 skip

But I got following error" ERROR: Unknown command: bondbond_coeff 1 class2 12.4260 1.4570 1.1010"

Can someone help me writing bondbond coeff and bondangle coeff for angle_style hybrid class2 harmonic in the input script (not in the data file)?

I appreciate your time.

Han

Hi

I am using angle_style hybrid class2 harmonic. I am trying to include
bondbond coeff and bondangle coeff in the input script. I generated input
script as below. Since the restart file does not include those angle
coefficients, I would like to include angle coeff, bondbond coeff, and
bondangle coeff in the input script.

you are using the wrong syntax. there only are angle_coeff, dihedral_coeff
and improper_coeff. the differentiation into the various class2 subtypes is
done as part of the corresponding parameters.

please read the description of the class2 styles very carefully and you'll see.

cheers,
    axel.

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To wit, there is no bondbond_coeff command
in LAMMPS, hybrid or not.

The angle class2 syntax is like this (see the doc page)

angle_coeff 1 bb ...

so if you want that to work with angle hybrid you
would do this

angle_coeff 1 class2 bb ...

The doc pages explain it all.

Steve

1 Like