Messages

16

General Questions and Answers / Re: Error during phonon calculation

« on: June 22, 2020, 19:47 »

I have runed several times but everytime the job terminated showing the message "Exit Code: 9".  In the displacement file once I have observed that the problem is related to RAM. I have tried with reduce numer of processor and it does not work. But for similar symmetric structure the programme runs well.

17

General Questions and Answers / Error during phonon calculation

« on: June 20, 2020, 16:29 »

I have doped boron and nitrogen in twin-graphene structure. Phonon band structure calculation for same no of atom of pristine structure and one configuration of BN doped twin graphene is completed successfully but for some cases job terminated. Kindly suggest me  how to get phonon band structure. The input and corresponding output is attached herewith for your reference.

18

General Questions and Answers / Re: Query related Open-shell singlets calculation in ATK

« on: June 17, 2020, 16:45 »

I have not evaluated that the bond is 1.5. Actually I want to mean that the bond length for a single bond is usually 1.54 Angstrom and that of a double bond is 1.34. In our case the bond lengths between C2 atom with its three neighbours are respectively 1.36, 1.42 and 1.42 Angstrom (please see the attched figure)  respectively. i.e. one double bond and two bonds have higher than single bond type and lower than double bond. Thus total no of bonds exceeds 4 which is not possible. Expected bond lengths between C2 atom with its three neighbours are 1.34, 1.54 and 1.54 Angstrom but in our case situation is different.

19

General Questions and Answers / Error in initial state energy durin electron_phonon_coupling

« on: June 13, 2020, 20:06 »

During a electron_phonon_coupling calculation the job is terminated by showing increase initial state energy range. Can you please suggest how to decide what should be the value for  initial state energy range? The input file is attached for your reference.

20

General Questions and Answers / Re: Query related Open-shell singlets calculation in ATK

« on: June 5, 2020, 19:01 »

I am attaching here one more clear view of the structure for your reference.

21

General Questions and Answers / Re: Query related Open-shell singlets calculation in ATK

« on: June 5, 2020, 15:30 »

Thank you for kind reply. I totally agree with you that DFT can  handled three cordinated C atom. But in my case the problem is that the bond lengths between C2 atom with its three neighbours are respectively 1.36, 1.42 and 1.42 Angstrom (please see the attched figure)  respectively, which indicates one double bond and two roughly 1.5 times bonds and as a reasult total coordination changes to more than 4 instead of 4. I have performed the calculations using both PBE and HSE functional and the results are more or less same. Can you please suggest what may be the possible reason and how can I overcome this situation. Any kind of help is highly appreciated.
Actually I have communicated this structure in a prestigious journal and reviewer raised question here  for that reason I am not able not to give the log file at this moment.

22

General Questions and Answers / Query related Open-shell singlets calculation in ATK

« on: June 3, 2020, 20:28 »

I have optimized an 2D structure in which three different cordination of carbon is present.  In case of three cordinated carbon we are expecting two single bond and one double bond but unfortunately we are getting some different situation.  One reason may be the wave function is an open-shell singlet. Whether open-shell singlets can be performed using ATK for periodic structures and how can I get rid of this problem?

23

General Questions and Answers / Re: Query regarding HSE functional

« on: April 12, 2020, 18:45 »

Here I am attaching the python script. Kindly suggest me how to change the input so that I will get the optimized geometry in a limited time period. My actual interest is to calculate the band gap using HSE functional.

24

General Questions and Answers / Query regarding HSE functional

« on: April 6, 2020, 10:47 »

I want to calculate band structure of a 2D material using HSE functional. I have optimized the structure initially using GGA-PBE method and starting from this geomerty I have started the calculation for optimization using HSE functional (Two compute node used each having 24 processor). The unit cell consists of 26 atoms. But the job is running since last ten days. Actually I am very much confused whether the calculation is running in right direction or not.  Kindly suggest me. Also give me an idea how to get band gap using HSE functional within a limited time period.   

25

General Questions and Answers / Re: How to calculate piezoelectric tensor for a 2D material

« on: April 6, 2020, 10:34 »

Dear Sir, I have not received any answer on the given topic. I am eagerly waiting for the response.
Thanking you in advance.

26

General Questions and Answers / Re: Query regarding deformation potential constant

« on: March 3, 2020, 06:32 »

Sir I know this tutorial but the theroy behid it to calculate mobility is different from that of deformation potential theory which i have already mentioned in my starting mail. The papers that I have told they have used deformation potential theory for calculating mobility.

27

General Questions and Answers / How to calculate piezoelectric tensor for a 2D material

« on: March 1, 2020, 05:09 »

Dear Sir/Madam
Kindly help me to calculate the piezoelectric tensor for a 2D material. I have calculated for a 2D material using ATK analysis and the coefficient I have obtained are in the units of C/m^2 whereas in most of the papers the coefficient for a 2D material are in the units of C/m. 

28

General Questions and Answers / Re: Query regarding deformation potential constant

« on: February 28, 2020, 17:04 »

Yes I want to calculate mobility based on deformation theory.

29

General Questions and Answers / Regarding phonon band structure calculation

« on: February 24, 2020, 11:14 »

Dear Sir/Madam,
I have calculated phonon band structure using ATK. I have got the plot for Energy versus high symmetry point. But in general frequency versus high symmetry point is reported in many papers.
Kindly tell me how to get the curve in terms of frequency.

30

General Questions and Answers / Query regarding deformation potential constant

« on: February 22, 2020, 13:49 »

Dear Sir/Madam,
I want to calculate carrier mobility using deformation potential theory for that I required deformation potential constant. I have found some papers (Carbon 130 (2018) 206-214, Carbon 124 (2017) 228-237) where they used ATK for calculating the same.  Kindly suggest me how to calculate this using ATK. In ATK in the analysis section deformation potential is there but I have seen the background theory is different as that of I required.
Kindly help me to sort out this.