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Messages - nicolapelagalli

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1
Yes, I use it. I'll give a try as soon as possible.
Thank you again.

2
Thank you very much, this was giving me several problems. Do you know how I should solve this issue? Sottry, I'm not an expert about processes excetera...

3
Dear QuantumATK staff,

we are following this tutorial: https://docs.quantumatk.com/tutorials/dynamical_matrix/dynamical_matrix.html .
We attached py file and log file with the error we get, do you have any suggestion?

Thanks.

4
Thank you, that's what I exactly was looking for.
After calculating Dynamical Matrix (it took almos 4 days  ???), I wrote the script I attched (16,0 CNT STD), and now I get the error shown in the log. I can't get what I'm doing wrong.
It seems something due to dyn_mat dimensions...

5
Sorry again.
How to get optical conductivity for different temperature values?

6
Sorry but I don't understand. That is my previous topic, I can't find any information about my question. I know that quantum ATK computes  simulations on an array of CNTs.

7
Dear QuantumATK staffs,

I'm simulating a semiconductive CNT in order to obtain its optical properties. The optical conductivity has very low values (in my case I'm calculating between 10-1000 GHz), and I think this is due to DFT calculations performed at 0 K. By the way, what should I do to obtain optical conductivity at a temperature greater than 0 K?
By mean mobility calculations is possible to obtain conductivty for different temperatures, but only at steady state if I'm not wrong.

Thanks for your attention.

8
General Questions and Answers / Re: CNT - Optical Spectrum
« on: March 6, 2019, 15:34 »
I repeated all the simulations making sure all settings were the correct ones, now everything works. It was an error due to myself.

Thanks for your kindness and patience.

9
General Questions and Answers / Re: CNT - Optical Spectrum
« on: February 25, 2019, 14:49 »
I'm using the 2018.06 version.
I didn't try to increase the cell size, since I thought that a 4nmx4nm cell size was enough for a (16,0) nanotube (in order to assume that the tubes do not interact). Now I'm going to increase the vacuum padding.


You can find my scripts and logs in the annex.

10
General Questions and Answers / CNT - Optical Spectrum
« on: February 22, 2019, 17:14 »
Dear Quantum ATK staffs,

I'm trying to simulate a (16, 0) cnt at different primitive cell sizes. I noticed that the band gap value considerably changes using a primitive cell sized 8nm x 8nm instead of a 4nm x 4nm one (from 0,52 eV to 0,63 eV) and the dielectric constant changes too. Does anyone of you have an explaination to this behaviour?
I'm using GGA-type DFT, BLYP functional and FHI pseudopotential. k-point sampling = 100 along the simmetry axis of the tube.

Thanks for your attention.

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