[CPMD-list] Electron tunneling

[Axel Kohlmeyer]

On Wed, 28 Jul 2004, AO Alaka wrote:

AA> By electron tunneling I mean something like 2 carbon nanotubes connected
AA> by a covalent c-c bond with latent charge in the overall system. I.e a
AA> spin polarised config. I think it would be possible just to study the
AA> bond alone (I'll go through the manual) but I was just wondering if
AA> there was a way to simulate electron transfer through the system
AA> (probably not).

hmmm,

how about creating a movie of an isosurface representing the 
spin density? 

similar to the one in 
http://www.theochem.ruhr-uni-bochum.de/~axel.kohlmeyer/cpmd-vmd/part5.html#chap7_sect6
which also explains the procedure to get there.

or you could try localizing the electrons and look at the wannier 
centers and visualize them like in 
http://www.theochem.ruhr-uni-bochum.de/~axel.kohlmeyer/cpmd-vmd/part3.html#chap5_sect1
(the transparent little blue spheres).

for that you'd need to add  DIPOLE DYNAMICS WANNIER, and
 WANNIER REFERENCE (followed by a sensible reference point for the
localization) and then read in the IONS+CENTERS.xyz file.

question is, how to 'nudge' the spin density from one side to 
the other, if the exchange does not happen fast enough or at all?
perhaps you can use a weak electrostatic field...

regards,
	axel.

AA> 
AA> Thanks for the help 
AA> 
AA> On another note; 
AA> 
AA> 1. Does anyone know how to use the LDOS keyword?
AA> 
AA> 2. Is there anything to look out for when minimising the geometry of 1d
AA> and 2d systems. I've had lots of trouble with these. Even better would
AA> be an optimal set of keywords for doing this (particularly with using
AA> PCG). I've had a look through the forum but proper examples of solutions
AA> seem limited.
AA> 
AA> 3. I've been having trouble using KPERT but a look through the code
AA> showed that the point group has to be specified (I think). I am trying
AA> this now but does anyone think there might be other reasons apart from
AA> this. The program just stops with a message like; "PROGRAM STOPS IN
AA> SUBROUTINE PERTURB" (or something like that).
AA> 
AA> Thanks in advance.  
AA> 
AA> _______________________________________________
AA> CPMD-list mailing list
AA> CPMD-list at cpmd.org
AA> http://cpmd.org/mailman/listinfo/cpmd-list
AA> 
AA> 

-- 


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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/
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