Re: [SIESTA-L] Adding point charges

[Oleksandr Voznyy]

Look at the SyntheticAtoms option in manual and 'fractional' program in 
the Util/VCA.

If you want it to coincide with existing atom, change it's charge by a 
VERY small amount (usually you want small point charges to remain in the 
linear response regime)
If your point charge should be in a different place, simply put a 
pseudo-hydrogen atom with a very small charge (using the pseudo 
generated by the above program).
But since we are still working with pseudopotentials your potential 
would represent a real point charge only beyond some distance (~1A).