The ABINIT Users Mailing List ( CLOSED )

["Zhenhua Zeng" <myid520@163.com>]

Dear All,

In Elphon lesson of the tutorial: Electron-Phonon interaction and 
superconducting properties of Al.
It is written that: 
In the standard case, ABINIT uses symmetry operations and non-stationary 
expressions to calculate a minimal number of 2DTE for different mixed second 
derivatives of the total energy. In our case we use the first derivatives, 
and they must all be calculated explicitly. This is why each perturbation is 
treated in a different dataset.

There is just one atom in this tutorial, however, If there are two or more 
atoms, is each atom treated in a difference dataset too?
Or can we use symmetry to reduce the number of ipert?
And setting like this:
rfatpol  1   n   (n is the number of total atoms)
rfdir    1 0 0   etc
                                
Best Wishes
Zhenhua Zeng