[CPMD-list] Surface calculations

[Axel Kohlmeyer]

On Tue, 2 Nov 2004, "J. Schüle" wrote:

hello,

would you mind posting (part of) your inputs. there may be many 
reasons for this, but it is difficult to tell without having a
look at the inputs. e.g. the cpmd input file parser has some 
idiosyncrasies that may not be obvious.

regards,
	axel

JS> Hello,
JS> I tried to get some meaningfull surface calculations. Therefor I put 48 
JS> atoms in  a cell and set the cell-size to in a way half the interatomic 
JS> distances to the "next cell" according to the periodic boundary 
JS> conditions. After a Wavefunction calculation I performed a geometry 
JS> optimization which I expected to be lower in energy - but the optimzed 
JS> geometry is instead as much as 20.2eV higher in energy ??
JS> Then I optimized the wavefunction again for this optimized geometry and 
JS> expected no great change in energy - but the energy dropped by 1.96eV.
JS> 
JS> Am I wrong, or is this method not suited at all to be compared to 
JS> surface experiments with a resolution of 0.1eV and beyond?
JS> 
JS> Thanks for any comments,
JS> 
JS>   Josef Schüle
JS> 
JS> _______________________________________________
JS> CPMD-list mailing list
JS> CPMD-list at cpmd.org
JS> http://cpmd.org/mailman/listinfo/cpmd-list
JS> 
JS> 

-- 

=======================================================================
Dr. Axel Kohlmeyer   e-mail: axel.kohlmeyer at theochem.ruhr-uni-bochum.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/
=======================================================================
If you make something idiot-proof, the universe creates a better idiot.