Here we will reuse the data in example_1_fcc_Al
. Copy the files to a new, clean folder, and repeat the steps from the first tutorial to generate second and third order force constants.
You should end up with (among other things)
Note that this example is fcc Al. I chose that since with one atom per unit cell, the thermal conductivity calculations are really fast. Unfortunately, since thermal conductivity in Al is dominated by the electronic component, none of the values can be compared with anything in a meaningful way (but that is not the point of this tutorial anyway).
To get the thermal conductivity, run
mpirun thermal_conductivity -qg 5 5 5 --temperature 300
and it should appear, rather quickly. Make yourself familiar with the options for thermal conductivity, there are quite a few. A series of temperatures can be calculated with
mpirun thermal_conductivity -qg 5 5 5 --temperature_range 10 1000 50 --logtempaxis
Do a simple q-point convergence
Per default, the scattering rates are integrated using the tetrahedron method.1
Make them test tetrahedron vs gaussian.