ATC Cu_ttm.mat file problem

Dear everyone,

I am using lammps USER-ATC package to work on laser ablation of copper. As I looked at the material properties of copper, I found a problem with electron conductivity. The parameters in Jones paper are 11.2J/Kms for lattice conductivity and 244.3J/Kms for electron conductivity.

I converted to atc units which is consistent with lammps in mass, time, and length. The result of lattice conductivity is the same as that in the file (67.44…), while electron conductivity is 1471 instead of 441. Can anyone explain this?



I don’t know what “atc” units means. The LAMMPS units command

shows the options the code supports. I believe the fix atc command

and USER-ATC package should work with any units, assuming

your inputs are correct.


Dear Steve,

The document states ‘‘e.g. heat (energy) flux. The units are in AtC units, i.e. derived from the LAMMPS length, time, and mass scales’’. The material properties for copper is included in the example folder, which is used with ‘unit metal’.

Therefore, the energy unit [mass][length]^2/[time]^2 would be g/mol(A/ps)^2. I converted the copper properties given in Jones’s paper to the abovementioned unit. I was able to match the correct parameters other than the electron conductivity.



Hmmm. I guess you need to ask the ATC package developers.
Reese is CCd.