Re: [cclib-devel] SCF convergence in ADF

[Adam T. <a-t...@st...>]

> On an unrelated note, the geo-opt files don't seem to contain scf
> convergence info except at the very end of the file. I'm not sure
> whether I should parse this, or try to find out whether there's some
> keyword that will cause scf convergence info to be printed in the main
> body of the file.

So I looked into this a bit. As I understand it, ADF determines SCF  
convergence by comparing the Fock matrix and the density matrix (as  
determined from the Fock matrix). Ideally, the difference would be 0,  
but since that would take forever, it uses two threshold values:  
scfcnv and scfcnv2. These can be set, but default to 1e-6 and 1e-3,  
respectively. These are on lines 1761 in dvb_gopt.adfout. These two  
values are used depending on whether it is a geometry optimization or  
not. During the first and last geom cycle, it should use scfcnv;  
otherwise, scfcnv2. More info is at:

http://www.scm.com/Doc/Doc2005.01/ADF/ADFUsersGuide/page124.html

During the SCF cycle, it prints imax (maximum matrix element) and d- 
Pmat, which I think are the maximum element and norm of the matrix.  
Unfortunately, the rules for determining whether the value is scfcnv  
or scfcnv2 don't seem to be followed exactly in this calc. It looks  
ok in the single point calc.

Is your understanding after reading the above link similar?

Adam