The ABINIT Users Mailing List ( CLOSED )

[arnaud marmier <a.marmier@bath.ac.uk>]

Hello all,

 I'm a new user of Abinit, interested in latice dynamics.
 As I'm migrating from supercell to get the phonons, I'm currently 
trying to do very simple things, and to get a good feeling of ifc.

I'll use the DDB generated in the tutorial 5, i.e. t54 (phonons at 
Gamma, no Born charges) and t55 (at Gamma, with Born charges).

  The ifc.in I use is very very simple :

 nph1l     1     ! Number of phonons in list 1
 qph1l     0.0 0.0 0.0    1.0

When I run it for t45, it crashes (under Windows).
For t55, it gives the frequency, but (by comparison with the abinit 
output), it hasn't taken into account the born charges (no LO-TO splitting).

Is it true that IFC needs a DDB wich has electric field pertubation ?

How do you enforce that this information is used by IFC ? Do you need to 
 use ifcflag ?

Best wishes
Arnaud