[CPMD-list] Questions of potential function and the visualization of bulk system

[Axel Kohlmeyer]

On Sat, 11 Dec 2004, Nevil wrote:

N> Hi everyone:
N> 

N> I have two questions one is about the potential function and another
N> for the visualization of bulk system.

N> 1,For the potential function: CPMD uses the Busing potential function
N> which doesn't include the cation-anion interactions. Is it possible to
N> use Morse potential function which first has the same form as Busing
N> function but then has one Morse-type potential more in it.

can you please elaborate a little more, for what you want to use
explicite potential functions. your statement is a little confusing.


N> 2,For the visualization of the bulk system:
N> I want to follow the example for the visualization of the bulk system in this website:
N> http://www.theochem.ruhr-uni-bochum.de/~axel.kohlmeyer/cpmd-vmd/part5.html#chap7_sect5
N> But I don't know how to get the .cube file which has many moleculars in it. My .cube file just has one isolated molecular.

you can only see so many atoms/molecules, than your supercell contains.
if you want to visualize a periodic images of the supercell, you can
either use the -rep switch of cpmd2cube or use the periodic display
facility of VMD.

for the latter case, you may want to download (and test) the latest 
pre-release version of VMD from:
http://www.ks.uiuc.edu/Research/vmd/alpha/
which contains several corrections in the handling of periodic system
and an improved cubefile reader plugin.

regards,
	axel kohlmeyer.

N> 
N> Is there anyone can help me?
N> 
N> Thank you very much.
N> 
N> Merry Christmas.
N> ^^
N> 
N> Regards.
N> 
N> 

-- 

=======================================================================
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.