Topics

1

Scripts, Tutorials and Applications / sp3-passivation with H for bare Si nanorod

« on: August 25, 2010, 04:31 »

Dear Everyone,

I made a script for passivating dangling bonds of bare Si nanorod with Hydrogen and share it with you.
(passivate_sp3.py)
The usage is as follows:
1. Open Custom Builder and drop "passivate_sp3.py" onto the Custom Builder window.
2. make a structure of bare Si nanorod like "sinr110_bare.py" using Builder, Database, and Custom Builder.
3. drop the script of bare Si nanorod onto "Drop unpassivated system here" in the Custom Builder window.

After step 3, you can obtain sp3-passivated Si nanorod like "sinr110_passivated.png".

This script is still prototype and any kinds of feedback is appreciated

2

Gallery / Voltage drop calculated with ATK-SE 2010.02

« on: April 26, 2010, 02:14 »

I give the examples of voltage drop calculated with ATK-SE 2010.02 in this thread.
As you know, how to calculate Hartree potential is changed in new ATK (since 2009.06),
where Hartree potential is calculated against only central region, while in ATK 2008.10 it is calculated against whole system(left electrode + central region + right electrode).

This change bring mainly two benefits as follows:
1. New method makes SCF convergence more stable,
2. more reliable voltage drop can be obtained.

"more reliable" means that voltage drop mainly occurs around high resistance region like molecule, insulator, interface, and so-on, and is smoothly connected to reservoirs.

3

General Questions and Answers / A countour plot is failed in VNL 2009.06.2

« on: September 3, 2009, 09:15 »

Dear QuantumWise Staff,

I've found that there is probably a bug with displaying a contour plot in VNL 2009.06.2.
When I tried to view the effective potential of GNR 2probe with contour plot, I obtained one line like attached.
In addition, even one line is disappeared if any parameter for plot is altered.

My OS is OpenSUSE 11.1 for 64-bit.
Is this problem specific for OpenSuse?
Is there a way to avoid this problem with some tips in VNL 2009.06.2?

Thanks in advace.

4

Installation and License Questions / about a port for new license system

« on: August 17, 2009, 11:39 »

Dear QuantumWise support staff,

I'd like to know which ports is used for new license system and how to change a port.
New license system means a license system offered by Safenet.

Thanks in advance.

5

General Questions and Answers / Can a numerical data of transmission spectrum in a VNL file be extracted?

« on: July 6, 2009, 06:11 »

Dear Everyone,

I'd like to know whether or not a numerical data of transmission spectrum in a VNL file can be extracted with NanoLanguage.
In other words, Can one also access data stored in VNL file other than "atomic configuration" with NanoLanguage?
I tried to do it, but I couldn't.
Can anybody help me?

Thanks in advance.

6

General Questions and Answers / Is ZnO nanowire a metal?

« on: February 23, 2009, 07:54 »

Dear everyone,

I've tried the calculations of ZnO nanowire as bulk system and obtained the results that ZnO nanowire is a metal(zno_nanowire_7_band.vnl).

As you know, ZnO crystal  is a semi-conductor, so I suspect that my calculation might be wrong.
("zno_nanowire_7.py" is the script used for the calculation and  "zno_nanowire_7.out" is the log.)

My questions are as follows:
1. which property should ZnO nanowire has, metal or semi-conductor?
2. If the latter is right, that means my calculation is wrong, which part of it is wrong?(input structure?, parameter setting?)

I'd be happy to get any comments about it.
Thanks in advance!

7

Scripts, Tutorials and Applications / Script for making data files to plot k-resolved transmission with gnuplot

« on: February 4, 2009, 07:51 »

Dear all,

I'd like to share the script for calculating k-resolved transmission coefficients and making data files to plot them with gnuplot.

Converged 2probe NetCDF file is needed in order to use it.
In addition, you have to set three parameters in the script:
-line 16, NetCDF file name
-line 20, the number of k points
-line 23, the energy for which the transmission coefficients are to be calculated

Usage:
1. execute SCF calculation for your interesting system and save the result in NetCDF file
2. store "k_resolved_transmission.py" and the ncfile in the same directory
3. set-up three parameters mentioned above
4. execute "k_resolved_transmission.py"

After the task 4, you can get "xxxx.dat" for plotting.
(If the system is spin-polarized, "xxxx_up.dat" and "xxxx_dn.dat" are output.)

If you apply "k_resolved_transmission.py" to the system fe/mgo/fe (fe_mgo_fe.png),
you can obtain the picture like "fe_mgo_fe_parallel_0eV.GIF".

8

Future Releases / import xyz file in VNL by drag and drop.

« on: February 3, 2009, 03:03 »

I got the request about the function of VNL from my customer.

In current version of VNL, it's only way (?) to import xyz file in VNL as follows:
1. activate "Result Browser",
2. press "Open" button of "Result Browser" window and select xyz file.
It sounds somewhat messy.

If one can import xyz file in VNL by drag and drop directly, it's very  useful.
I guess this improvement is not trivial because xyz format is often used and it's also true for other format like CIF.