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[Latévi Max LAWSON DAKU <max.lawson@unige.ch>]

Dear Abinit users,

The Bader AIM analysis of a crystalline system gave me
charges that do not sum to zero. The deviation of
electroneutrality amounts to -0.05. Given my lack of
experience with such analysis I do not know if this ok.
Is this the case ? That is, am I too picky (here) about the
respect of the electroneutrality?

Actually my main worry actually comes from the fact that
this exceeding charge is carried by an atom which belongs
to a set of 4 structurally equivalent atoms. I obtained:
Q(at1)=-0.59, and Q(at2)=Q(at3)=Q(at4)=-0.53.
Please note that if I ask for the integrated densities within
atomic spheres of same radii centred on these atoms, I
obtain identical results, which is satisfying. But, it remains
that I do not understand what I'm doing wrong for the AIM
analysis. Did some of you experience such a problem ? If yes,
how did you solve it ?

Please note also that the number of critical points found for
at1 (BCP-RCP-CCP:6-14-4) differ from those found for at[2-4]
(BCP-RCP-CCP:5-13-3). I am not interested in the CPs, but I find
this quite worrisome.


Thanks in advance for your comments and suggestions.

Best regards,
Max


P.S. Here is the "standard" input file used for the analysis:


atom 3                      # Atom of interest


# Drivers
# --

surf   1                       # Build the Bader surface
crit    2                       # Determine the critical points
gpsurf 1                      # Output for GNUplot
irho   1                       # Integration of the Bader charge

# Parameters
# --

maxatd 8.0                # The starting atoms within this distance
                              # (bohr) are sufficient

maxcpd 5.0                     # The CPs are searched for within this
                              # maximal distance (bohr)

lgrad2 1.0d-5                  # Loose criteria are needed to catch
lstep2 1.0d-5                  # all the CPs.



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Latevi Max LAWSON DAKU
Departement de chimie physique 
Universite de Geneve - Sciences II
30, quai Ernest-Ansermet  
CH-1211 Geneve 4 
Switzerland 

Tel: (41) 22/379 6548 ++ Fax: (41) 22/379 6103
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