Messages

1

General Questions and Answers / phonon bandstruture

« on: June 20, 2017, 09:47 »

Hi,
    I have several questions about calculating phonon bandstructures with VNL-ATK2014.3. This is the first time for me to do this calculation, and I not quite understand the method of  calculating phonon bandstructures.
    1. Is cell expansion necessary?  The unit cell is the tetragonal lattice with 6 atoms. The lattice contans are a=b, γ=90. So need I to repeat the unit cell along x and y to get a larger cell? If yes, the k-point should change from (9,9,1) to (50,50,1), doesn't it?
    2. The tutorial has point out that ATK-classical should be choosen for phonon calculation. But for ATK2014.3,  when  ATK-classical is used, the button "Parameter set" dose not work. The screenshot has been attached. Under this circumstance, should I still choose ATK-classical or change it to ATK-DFT?
    3. At present, the tutorial of 2014 version can not be gotten, but it is important for me who is a novice. So would you like to offer me the 2014 tutorial or the link of it?
   Thank you and looking forward to your reply!

2

General Questions and Answers / Re: Transmission Pathways

« on: March 27, 2017, 15:48 »

Thank you!
Could you help me to check and modify the script file？The .nc file that I got is still the total！

3

General Questions and Answers / Re: Transmission Pathways

« on: March 27, 2017, 11:47 »

Some published papers have shown the spin-resolved transmission pathways by lower version，such  as 2013.8.
And would you offer us a Script file （.py）that could distinguish spin-up and spin-down？

4

General Questions and Answers / Transmission Pathways

« on: March 24, 2017, 11:16 »

Hi，
    How can I calculate the spin-dependent Transmission Pathways by ATK 2014.3？ At present， I can only get the sum  Transmission Pathways using this version.
    Would you be kind enough to show me some links or text representation about solving this problem by ATK 2014.3？

5

General Questions and Answers / Re: self consistent with SOC

« on: March 16, 2017, 13:32 »

Thank you for your patience!

6

General Questions and Answers / Re: self consistent with SOC

« on: March 14, 2017, 10:41 »

But, why can I do the bandstructure calculation with SOC using the method for the bulk? And I can get the right result .
I set as follow:
Bulk
New Calculater
Initial state
Bandstructure
New Calculater
Initial state
Bandstructure
 

7

General Questions and Answers / Re: self consistent with SOC

« on: March 13, 2017, 14:21 »

This is the python script that I used for the first time. But it appeared error!

8

General Questions and Answers / Re: self consistent with SOC

« on: March 13, 2017, 12:49 »

Yes， I want to get a feasible manner to calculate the SCF with spin orbit coupling for the device because it is hard to converge when adding SOC.

9

General Questions and Answers / Re: self consistent with SOC

« on: March 13, 2017, 03:15 »

Sorry, I didnot save the script.
The calculation of the first  set of  New Calculator and  Initial State is normal, Left Electrode Calculation, Right Electrode Calculation and then Device DFT Calculation. And all of them are converged. When beginning with the second set  of  New Calculator and  Initial State, I got the error message.

Traceback (most recent call last):
  File "c:\users\xiaoteng\appdata\local\temp\5597627426442390.py", line 519, in <module>
    initial_state=old_calculation,
  File ".\zipdir\NL\CommonConcepts\Configurations\DeviceConfiguration.py", line 496, in setCalculator
NL.ComputerScienceUtilities.Exceptions.NLValueError: The initial state must have the same spin type as the new configuration.
+------------------------------------------------------------------------------+
| NanoLanguageScript execution finished

I used the 2014.3 version.
The problem maybe lying in the spin type. Can the initial state of  the first set be set as 0? I tried 
the band struture with soc, the  initial state of  the first set being 1, and finally got the right result.

10

General Questions and Answers / Re: self consistent with SOC

« on: March 12, 2017, 04:04 »

I tried it, but an error appeared！After finishing the first set of the  two blocks:  New Calculator and  Initial State, the wrong information emerges as following,
Traceback (most recent call last):
  File "c:\users\xiaoteng\appdata\local\temp\5597627426442390.py", line 519, in <module>
    initial_state=old_calculation,
  File ".\zipdir\NL\CommonConcepts\Configurations\DeviceConfiguration.py", line 496, in setCalculator
NL.ComputerScienceUtilities.Exceptions.NLValueError: The initial state must have the same spin type as the new configuration.
+------------------------------------------------------------------------------+
| NanoLanguageScript execution finished       

The parameter of the first  Initial State ：user spin， and the spin type of each atom is set as 0.
The parameter of the second  Initial State ：use old calculation, and the filename is the first .nc file.
So Where is the problem ?                           |

11

General Questions and Answers / self consistent with SOC

« on: March 10, 2017, 09:49 »

Hi，
I  want to calculate the transmission with SOC，OMX as the pseudopotential （2014 version）. During the self consistent, it is hard to converge when I added the SOC. How should I do？
I had refered this.      http://docs.quantumwise.com/tutorials/spin_orbit_bandstructures/spin_orbit_bandstructures.html
So could I set as follow:
Device
New Calculater
Initial state
New Calculater
Initial state
Is it the right manner？

12

General Questions and Answers / Re: pseudopotential-basis set

« on: March 8, 2017, 02:19 »

Thank you so much！

13

General Questions and Answers / Re: pseudopotential-basis set

« on: March 7, 2017, 14:13 »

Thank you！
I have other question.
I will  calculate the band structure with SOC by choosing OMX pseudopotential. Before this, I need to optimise the structure. So I want to know which pseudopotential should I choose during the optimization, FHI or OMX?
And hope you can give me the link about the theoretical knowledge of OMX, FHI.

14

General Questions and Answers / Re: pseudopotential-basis set

« on: March 7, 2017, 03:42 »

Virtual NanoLab 2014.3

15

General Questions and Answers / pseudopotential-basis set

« on: March 6, 2017, 10:28 »

Hi，
    When I begin an optimizegeometry, I choose pseudopotential :OMX. At this time, the basis set has several choices, such as Rc=7.0 Tier 0,Rc=7.0 Tier 1, Rc=9.0 Tier 0, Rc=9.0 Tier1, Rc=11.0 Tier 0, Rc=11.0 Tier1. I want to know the diffence among them and how to choose the appropriate one.
   Actually, I saw the tutorials from  QuantumWise Forum，and it shows that the basis set is medium[s2p2d1]. Why is it different from mine?