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["Josef W. Zwanziger" <jzwanzig@jzwanzig.org>]

This is odd. I've done lots and lots of PAW calc's, with ecutsm and without, 
on magnetic and non-magnetic systems, and have never observed anything like 
what you're describing. Can you post your input file?

 Josef W. Zwanziger
Professor of Chemistry
Canada Research Chair in NMR Studies of Materials
Director, Atlantic Region Magnetic Resonance Centre
Department of Chemistry
Dalhousie University
6274 Coburg Road
Halifax, Nova Scotia B3H 4J3 Canada
tel: +1.902.494.1960
fax: +1.902.494.1310
web: http://jwz.chem.dal.ca
jzwanzig@jzwanzig.org,jzwanzig@dal.ca



----- Original Message ----
> From: Emmanuel Arras <emmanuel.arras@cea.fr>
> To: forum@abinit.org
> Sent: Thursday, December 11, 2008 1:27:40 PM
> Subject: [abinit-forum] ecutsm and electronic convergence
> 
> Dear abinit users,
>    I have observed that the use of ecutsm (typically 0.5 Ha for a cutoff 
> of 10 Ha, ecut CV around e-2 eV/atom) makes it very difficult for abinit 
> to achieve convergence : i.e. over 200 iterations to reach e-8 in toldfe 
> (despite a steady slope), as compared to the 30 usually needed 
> iterations. I am wondering where this comes from, and how to solve this 
> issue.
>   Note that I am using paw, and that my system is magnetic. It seems in 
> fact that magnetism is hugely affected by this ecutsm : it takes much 
> more time to reach final value (whereas magnetism is usualy very quick 
> to converge). Also note that whatever the cutoff (up to 20 Ha, which is 
> huge in paw), this problem appears.
> 
> Thanks for any advices.
> 
> Emmanuel ARRAS