Messages

1

General Questions and Answers / Electron Density

« on: July 11, 2020, 17:58 »

Hi,

'Electron Density' plot color-bar is showing a range (say)_

-5.2 * 10^-22     to     4.8   (Ang^-3).

Should not the lower limit be zero? What does this negative number mean?

Best_
Dipankar Saha

2

General Questions and Answers / EDD / Intraband contribution

« on: January 3, 2020, 09:40 »

Hi,

1)
 EDD analysis
QuantumATK version 2018.06

What does a negative sign mean? Is it depletion?

2)
Optical spectra
QATK 2019.12

Any Ref. for 'Intraband contribution' calculation ? 

Thanks and Regards_
Dipankar Saha

3

General Questions and Answers / Re: SOGGA.PBE

« on: January 3, 2020, 09:25 »

 Okay...  / Thank you Jess ! 

4

General Questions and Answers / Re: Data set _ Suggested GGA / Partial Electron Density

« on: January 3, 2020, 09:24 »

Thank you ! 

5

General Questions and Answers / Data set _ Suggested GGA / Partial Electron Density

« on: January 1, 2020, 12:06 »

Hello,

1) For Plane Wave Calculator _QATK2019.12, if we select PAW pseudopotential method, we find various data sets as_
a) GPAW GGA
b) JTH GGA
c) Suggested GGA.

How are those different?


2) What is 'Partial Electron Density'?

Thanks and Regards_
Dipankar Saha

6

General Questions and Answers / Re: SOGGA.PBE

« on: January 1, 2020, 11:50 »

Besides, I wanted to know_

Is there any Ref/Tutorial available on 'PlaneWaveCalculator'_QATK2019.12 ?

7

General Questions and Answers / SOGGA.PBE

« on: December 20, 2019, 14:12 »

Hi,

1) For SOGGA.PBE calculation, I find 'force_ timereversal = False". What does that signify?

2) Besides, the default pseudopotential is set to --> 'SG15-SO [ ] SOGGA.PBE'.  Can't we use 'OMX [ ] GGA.PBE' for SOC calculations?

Thanks and Regards_
Dipankar Saha

8

General Questions and Answers / Re: Adsorption of molecules

« on: October 29, 2019, 20:44 »

Okay... / Using ATK, can we accurately model  adsorption of molecules ?

9

General Questions and Answers / Adsorption of molecules

« on: October 28, 2019, 16:07 »

Hi,
 Is there any new tutorial on adsorption of molecules on graphene surface?

Best_
Dipankar Saha

10

General Questions and Answers / Phonon / Dynamical matrix

« on: May 15, 2019, 16:29 »

ATK 2018.06_
# Phonon calculation

Any Documentation / Reference ??

Best_
Dipankar

11

General Questions and Answers / Re: Mobility

« on: April 8, 2019, 13:45 »

Thank you Petr !! 

12

General Questions and Answers / Mobility

« on: April 6, 2019, 18:01 »

Hi,

What is_
"mobility calculation with isotropic scattering" ? Can you provide references?

Thanks and Regards_
Dipankar

13

General Questions and Answers / Re: Optical Spectra / Optical Conductivity

« on: March 24, 2019, 19:49 »

Okay ..... Thank you Petr for the details! 

Best_
Dipankar

14

General Questions and Answers / Re: Hybrid DFT SCF Loop

« on: March 24, 2019, 09:54 »

Thank you Petr for the details ! 
 

15

General Questions and Answers / Re: Optical Spectra / Optical Conductivity

« on: March 24, 2019, 09:49 »

What did you mean by saying_ "such as HSE to correct for single-particle excitation spectrum, but one do not account for two-particle excitation" ?

I meant exactly what I wrote that neither DFT nor hybrid functional approach (e.g., HSE functional) are able to describe two-particle excitations, e.g., excitons, see https://en.wikipedia.org/wiki/Exciton or a textbook on Solid State Physics or Many-Body Theory for more information on various excitonic effects.

You have got it all wrong! Focus was not on the word "two-particle excitation".

Previously, you mentioned_ "HSE to correct for single-particle excitation spectrum".  I wanted more details from you, about this 'correct for'!!