I keep getting this error with Siesta every time I do a calculation,

Program aborted. Backtrace:
Semicore shell(s) with -1 electrons included in the valence for
Semicore shell(s) with  1 electrons included in the valence for
Al                   must be in PAO.Basis (it has semicore states)

I'm pretty sure I'm including them properly, I have a structure with Al As and C, the C works fine, but I'm unsure why the others aren't working well.

I've tried using B instead of Al and I get the same error.

Pseudopotentials are the ones from here


  • 2
    $\begingroup$ Can you share your full input file. It might be that you have defined the same thing twice in two different ways. It might be useful to check this thread : $\endgroup$
    – Elie H
    Dec 21, 2021 at 14:45

1 Answer 1


Before I try and answer your specific query, the first thing I would do is to get my Pseudopotentials from :


The Pseudos here are utilized a bit more and better tested. It is also what SIESTA developers recommend here :


Testing out your Pseudos should be an important step. Of course let's try and make the calculations work first !

Now, for your specific question, it would help if you could share your input (.fdf) file if possible since I think what is happening is that a Pseudo is either not well defined or that there is contradictory information in the basis set versus the Pseudos. Here is a thread of a similar issue in the SIESTA mail archive : https://www.mail-archive.com/siesta-l@uam.es/msg03437.html

I could elaborate the answer with a bit more information on your part.


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