The ABINIT Users Mailing List ( CLOSED )

[Xavier Gonze <gonze@pcpm.ucl.ac.be>]

Dear Marcel,

On 10 Sep 2007, at 11:37, Marcel Mohr wrote:

> Dear list members,
>
> how could one implement the LOTO splitting in Nanowires correctly?  
> The calculation of the Born charges and dielectric tensors are  
> performed.
> But if I understand correctly , for the calculation of the LO  
> frequencies, the volume of the unit cell is used (i am refering to  
> the paper gonze PRB 55 10355 (1997)).
> However, this unit cell is kind of arbitrary in two directions for  
> NWs.
> Are the results from ABINIT still valid?

The electrostatics of an isolated wire and the one of a 3D solid  
differ qualitatively.
Thus, the very notion of LO-TO splitting should be reexamined in the  
case of a nanowire.
This has nothing to do with first-principles calculation, DFT or the  
ABINIT implementation.
Supposing that you understand the electric-field/phonon interaction  
in nanowires, and the
parameters that characterize it, then I am sure one can infer the  
values of the parameters
from ABINIT...

Best regards,
Xavier