[CPMD-list] Mysterious (to me) Error

[Axel Kohlmeyer]

On Tue, 3 Feb 2004, Jim Kress wrote:

JK> Axel,
JK> 
JK> Thanks.
JK> 
JK> > execess kinetic energy, you may want to use
JK> > TEMPCONTROL IONS until the system is (somewhat) equilibrated.

JK> 
JK> This run I am trying is the P(OH)4 anion  run from the examples given in one
JK> of the CPMD symposia given in 2002 or 2003.  It's supposed to decompose
JK> after about 200 fs.  Is 'equilibration' possible for a system of this sort?

jim,

where did the geometry come from? 
you could try doing a (rough) geometry optimization first.

were cutoff and pseudopotential selection also given in 
the example?

axel.


JK> 
JK> Jim
JK> 
JK> 
JK> ----- Original Message ----- 
JK> From: "Axel Kohlmeyer" <axel.kohlmeyer at theochem.ruhr-uni-bochum.de>
JK> To: <cpmd-list at cpmd.org>; "Jim Kress" <cpmd at kressworks.com>
JK> Sent: Tuesday, February 03, 2004 4:38 PM
JK> Subject: Re: [CPMD-list] Mysterious (to me) Error
JK> 
JK> 
JK> >
JK> > On Tue, 3 Feb 2004, Jim Kress wrote:
JK> >
JK> > JK> While executing the attached input file using CPMD 3.7.2 on a RH 7.3
JK> Linux
JK> > JK> cluster CPMD compiled with PGF and MPI, I get what appears to be a MPI
JK> > JK> related error (see attached output file).  However, when I run an
JK> similarly
JK> > JK> structured 32water plus hydronium ion input file from Axel's website,
JK> it
JK> > JK> runs just fine.
JK> > JK>
JK> > JK> Any ideas why this fails?  It is absolutely repeatable on my cluster
JK> and the
JK> > JK> failure is independent of the number of nodes being used.
JK> >
JK> > hi jim,
JK> >
JK> > please try reducing the timestep. your system is heating up
JK> > and my guess is, that the integration of the equations of motion
JK> > may become unstable (the segfault is probably only a sign
JK> > of MPICH not exiting gracefully).
JK> >
JK> > since the nose thermostat seems not to be able to remove the
JK> > execess kinetic energy, you may want to use
JK> > TEMPCONTROL IONS until the system is (somewhat) equilibrated.
JK> >
JK> > hope this helps,
JK> > axel.
JK> >
JK> > p.s.: you should also reduce the electron mass (default is 400a.u.!)
JK> >
JK> > JK>
JK> > JK> Thanks.
JK> > JK>
JK> > JK> Jim
JK> > JK>
JK> >
JK> > -- 
JK> >
JK> >
JK> > =======================================================================
JK> > Dr. Axel Kohlmeyer                        e-mail: axel.kohlmeyer at rub.de
JK> > Lehrstuhl fuer Theoretische Chemie          Phone: ++49 (0)234/32-26673
JK> > Ruhr-Universitaet Bochum - NC 03/53         Fax:   ++49 (0)234/32-14045
JK> > D-44780 Bochum  http://www.theochem.ruhr-uni-bochum.de/~axel.kohlmeyer/
JK> > =======================================================================
JK> >
JK> >
JK> 
JK> 
JK> _______________________________________________
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JK> CPMD-list at cpmd.org
JK> http://www.cpmd.org/mailman/listinfo/cpmd-list
JK> 
JK> 

-- 


=======================================================================
Dr. Axel Kohlmeyer                        e-mail: axel.kohlmeyer at rub.de
Lehrstuhl fuer Theoretische Chemie          Phone: ++49 (0)234/32-26673
Ruhr-Universitaet Bochum - NC 03/53         Fax:   ++49 (0)234/32-14045
D-44780 Bochum  http://www.theochem.ruhr-uni-bochum.de/~axel.kohlmeyer/
=======================================================================