Question regarding fix_atc output

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1

Dear ATC users,

I am trying to evaluate the virial stress/atom computed using lammps and then projected onto the mesh created by “fix_modify AtC fem mesh”. However, I am not able to output this computed quantity. The commands I am using, after minimization of the system, are the following:

fix AtC all atc hardy
fix_modify AtC transfer fields none
fix_modify AtC transfer fields add density
fix_modify AtC transfer kernel cubic_sphere 10.0
fix_modify AtC fem create mesh 9 9 9 mdRegion f f f
fix_modify AtC transfer internal type internal

compute PerAtomSt all stress/atom
fix_modify AtC transfer computes add PerAtomSt volume
fix_modify AtC transfer output ClusterFE 1 text tensor_components
fix_modify AtC transfer atomic_output ClusterMD 1 tensor_components

run 1

When I run this code, I get the following error:

ERROR: Per-atom virial was not tallied on needed timestep (compute_stress_atom.cpp:94)

My guess is that the error is due to the fact that I specify compute before the “run” command. If I specify the compute stress/atom after the run command as shown below, the output files do not contain any of the virial stress information.

fix AtC all atc hardy
fix_modify AtC transfer fields none
fix_modify AtC transfer fields add density
fix_modify AtC transfer kernel cubic_sphere 10.0
fix_modify AtC fem create mesh 9 9 9 mdRegion f f f
fix_modify AtC transfer internal type internal

fix_modify AtC transfer output ClusterFE 1 text tensor_components
fix_modify AtC transfer atomic_output ClusterMD 1 tensor_components

run 1

compute PerAtomSt all stress/atom
fix_modify AtC transfer computes add PerAtomSt volume

Is there another output command for quantities calculated using compute and then projected onto the mesh? Any suggestions are highly appreciated.

Thanks,
Srikanth

2

The AtC folks can look at this.

Steve