The ABINIT Users Mailing List ( CLOSED )

[<yelinhui@hotmail.com>]

Dear All,

I have just started looking at ABINIT and see that the code looks quite
powerful. I have the following questions (I apologize if some are too naive 
but
please forgive me as a newbie):

1. I saw from the usersguide that ABINIT can treat 0D,1D,2D,3D cases. My
question is that whether they are treated just with the usual supercell
approach (with artificial vacuum added), or in the "intrinsic way" (with the
periodic boundary condition at the reduced dimension being indeed discarded) ?

2. By the way, can ABINIT give the work function for a chosen surface in a 2D
calculation?

3. About the implementation of the finite electric field: 

I am talking about the ground-state calculation with an external electric 
field
rather than the response function calculation of the e-field. Is the external
e-field implemented for the ground state calculation?

If so, then there are two ways of treating the external field. If ABINIT uses
the intrinsic 2D approach (which discards the periodic boundary condition 
along
z), then an external field, which generates a non-periodic external Coulomb
potential, can be applied perpendicular to the surface. Is this the way how 
the
finite external electric field is implemented?

Or, does ABINIT simply use the saw-tooth like Coulomb potential to simulate 
the
external field by the supercell approach (while maintaining all the 3D
periodicities)?

4. About GW:

Thanks to Don Hamann for telling me that ABINIT can get the full GW band
structure by the Wannier interpolation approach. Since I haven't seen any
document of how this should be done (I have got version 5.7.2 compiled), could
anybody kindly offer an sample input file for calculating the full GW band
structrue of, say, Silicon, along the high symmetry lines please? 

Or, could anybody please just decribe the steps (especially pointing out the
cautions in the input setup) ?

Besides, is the GW available for spin-polarized case?

4. Cut3d:

It is said that cut3d can be used to visualize the 3d wave function (such as
for OpenDX). Is that the full wave function, or the pseudo one, being
visualized ?

5. Is the Bethe-Salpeter equation ready or still being planned ?

6. I saw xOEP implemented. Is it availble for TDDFT only or is it also
available for ground state energy calculations? Is it ready for spin-polarized
cases?

If xOEP can be used for ground state 3D calculations, then, can I expect the
self-interaction-error to be larged removed? And, is the 1/r sympototic
behavior restored by xOEP?

7. I saw beta-SiC in the examples and also the the local exact-exchange
implementation. How mature are these two functionalities ?

8. Is it possible to do charged-cell calculations (with neutralizing jellium
background) ?

I understand that answes to these questions may not be simple. In that case,
could you please just refer me to the papers related to the corresponding
implementations?

Thanks a lot for everybody who has read my questions.

Linhui