Messages

166

General Questions and Answers / Re: How to create thin film in ATK

« on: July 30, 2018, 12:00 »

You can use the Surface (Cleave) in the Builders.
In order to design the thin film, you need to select the "Non-periodic and normal (slab)".
It is the same way to build the slab model.
You can control such as the lattice vector, no. layer and vacuum.

167

General Questions and Answers / Re: 2D plot

« on: May 24, 2018, 13:47 »

You need to get objects (for instance, BS, DOS, PLDOS) on the lab floor to plot, after your calculation is done,  which should be included the analysis object. You can easily plot it.

168

General Questions and Answers / Re: my calculation is not converged in SCF iteration.

« on: May 11, 2018, 07:36 »

In general, the minimum layered electrode with a periodicity works well. Especially, symmetry electrodes will be worked without convergence problem. But in your case, you have asymmetry electrodes and have a convergence problem with a long-ranged basis-set, SG15. Try the convergence using the increased layered electrodes. You can also check your electrode convergence using the electrode validator plugin.
It will help to look at the "Convergence of electrode parameters" in the linked tutorial, https://docs.quantumwise.com/tutorials/atk_transport_calculations/atk_transport_calculations.html

169

General Questions and Answers / Re: is it possible to reproduce a very very tiny bandgap~2mev

« on: May 3, 2018, 15:57 »

The SG15 has been implemented in 2017 version. You can check Pseudopotential in Basis set/exchange correlation in New Calculator.

170

General Questions and Answers / Re: the iteration control, the mixing variable and and algorith can not be changed

« on: May 3, 2018, 10:38 »

Hello,
There are not any more option for Algorithm and Mixing variable in Iteration Control in the VNL GUI.
That's why you see only PulayMixer and hamiltonianVarible.
But if you look at the linked page, there are more options(PulayMixer, AndersonMixer) for the Algorithm in ATK.
You need to edit in the script if you would like to use different Algorithm.
https://docs.quantumwise.com/manuals/Types/IterationControlParameters/IterationControlParameters.html.

171

General Questions and Answers / Re: my calculation is not converged in SCF iteration.

« on: February 28, 2018, 13:46 »

Hi,

It depends on the element and basis set.
In the case of SG15 basis set, it effects longer range than other basis set. (Look at the basis plot)

You are right if it is converged without problem physically.
We also recommend to analyze the HatreeDifferencePotential to see the convergence.
Even in the convergence in SCF iteration loop, sometimes, we need longer length of screening area.

Kind regards,
Maeng Eun Lee.

172

General Questions and Answers / Re: Bi2Se3 nanosheet

« on: June 1, 2017, 13:43 »

You can search the Bi2Se3 crystal structure in the Databases. (COD or Material Project).
Then, can you follow the link?
http://docs.quantumwise.com/tutorials/nanosheet_hole/nanosheet_hole.html

173

General Questions and Answers / Re: Choosing the right functional

« on: December 5, 2016, 15:02 »

I recommend to use the exchange correlation, Hybrid-B3LYP in the FHI-aims. And you should check your spin state. If you have unpaired spin on your molecules, you should set to the spin polarized, SHybrid-B3LYP. I hope you get a comparable result.