QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: tigeryzz on June 6, 2010, 07:21

Title: what's wrong?
Post by: tigeryzz on June 6, 2010, 07:21

The TwoProbe Calculation show no energies?
# sc 18 : q =   95.81028 e  dRho =  9.7550E-02
# sc 19 : q =   95.79945 e  dRho =  1.1419E-02
# sc 20 : q =   95.82167 e  dRho =  4.5293E-03
# sc 21 : q =   95.71135 e  Etot =        inf Ry  dRho =  1.9420E-01
# sc 22 : q =   95.63542 e  Etot =        inf Ry  dRho =  1.9823E-01  dEtot =         NAN Ry
# sc 23 : q =   95.55492 e  Etot =        inf Ry  dRho =  2.7637E-01  dEtot =         NAN Ry
how to deal with that problem?

Title: Re: what's wrong?
Post by: zh on June 7, 2010, 06:18

Could show  us your input file? Something may be wrong with your setup.

Title: Re: what's wrong?
Post by: tigeryzz on June 7, 2010, 15:27

The input file is attached. Thank you for your attention.

Title: Re: what's wrong?
Post by: Anders Blom on June 8, 2010, 22:30

I have some experience with setting this system up. I'm not at this point sure exactly what goes wrong, but I would advise you first of all to consider if you really want AA stacking in the graphene. Normally, graphene has ABABAB stacking, but in that case you need a bit bigger unitcell in the XY plane, as in the attached example.

I also recall that this is a very hard system to converge. Maybe the parameters used in the attached script helps you a bit!

I had a neat little tool for setting the geometry up, based on some simple parameters (number of screening layers, etc), but I can't find it... I will look for it!

Title: Re: what's wrong?
Post by: Anders Blom on June 8, 2010, 22:35

Found it! Enjoy!

This works with 2008.10. Would be neat to make it into a Custom Builder for 2010.xx...

Title: Re: what's wrong?
Post by: Anders Blom on June 9, 2010, 14:43

And here it is!