Messages

1

Scripts, Tutorials and Applications / Re: script for calculation of elastic constant and verious modulas

« on: November 26, 2016, 11:44 »

again for small help
 i have calculated the young's modules  and Poisson ratio for nano-tube but out of three value of young's modules is reliable in case of nano tube.( all obtained values  are different) and how to take the Poisson ratio among given 6 values. what is the way to analyse. plz clarify me detail as in simple word.

( as discussed above for young's modules , from strain stress curve we found positive and high value of  young's modules but calculated  value shows negative young's modules. how to confirm with these results .)

2

Scripts, Tutorials and Applications / Re: script for calculation of elastic constant and verious modulas

« on: November 10, 2016, 11:13 »

thank u sir...  well i get the result using this idea

3

Scripts, Tutorials and Applications / Re: how to stop an execution in Job Manager

« on: October 23, 2016, 09:20 »

in 2016 v also file log some times doesnot show the computing data untill it finished also some times the calculation have already finihed but file log is empty. win7 is my os... also atk python stopped massage appears even no calculation is loaded. after that it hangs the system to 5 to 10 min. it is quick to restart then its recover.. this problem hit me usually,,,

4

Scripts, Tutorials and Applications / Re: script for calculation of elastic constant and verious modulas

« on: October 23, 2016, 09:11 »

yes, thank u for this important discription, and the last method may be very easiest  and logical for calculation of youngs modulas as its defination. But i cant find the option to change the strain in atk calculation.. how to extract/analise the stress report. can u plz help me to describe the procedure to calculation...
                                                                                            waiting for reply....

5

Scripts, Tutorials and Applications / Re: script for calculation of elastic constant and verious modulas

« on: October 22, 2016, 09:51 »

hello sir
               i have calculated the elastic constant for TiC nanotube but dft ggives the negative values of elastic constant? what is the possible reason of the negative elastic constant values of bulk modulas , youngs modulas etc.. plz give me suggestion. here is my script file below.

6

Scripts, Tutorials and Applications / Re: How to measure the Diameter of nanowire??

« on: October 22, 2016, 09:13 »

thank u sir...

7

Scripts, Tutorials and Applications / Re: script for calculation of elastic constant and verious modulas

« on: October 18, 2016, 19:14 »

can we calculate it using 15.1? when  i trying to calculating elastic constant of Nanotube,  it starts but fails showing error "atk python has stopped working"  but i try using same procedure for bulk of Tic it successfully works. i have tried many times changing  various parameter but couldnot success. i m using Dft on gga with rpbe. plz suggest me the possible correct parameter to choose the calculation successful. also u can sens me script to run manually plz.

8

Scripts, Tutorials and Applications / script for calculation of elastic constant and verious modulas

« on: October 15, 2016, 07:12 »

hello sir,
            i want to study the mechanical properties of nanotube but we have old (11. version of Vnl and atk facility in our lab . so plz can anyone send me a script file in which i can insert the optamised nanotube.nc file for calculation of elastic constant, bulkmodulas and youngs modulas of nanotube.
plz help me.
                                     thanks

9

Scripts, Tutorials and Applications / Re: How to measure the Diameter of nanowire??

« on: October 8, 2016, 09:44 »

Thank u sir,
           i only want to include the rough value...
          so i will take average value from builder..
          thanks all of u experts...

10

Scripts, Tutorials and Applications / How to measure the Diameter of nanowire??

« on: October 7, 2016, 07:44 »

hello,
        how can we measure the Diameter of nanowire?? any litreture or idea, plz share..
        in case of carbon nanotube, the value of a=0.246 but i found c=4. something  for c. I want to measure Diameter of TiC nanotube and nanowire.
                       hope for reply, thanks
               

11

General Questions and Answers / Re: how to solve optamization problem in vnl?

« on: October 6, 2016, 10:09 »

haha may be...
thank you Mr Daniele...
i have tried on new version 16 (trial) but same problem encountered.
this must be due to lack of memory so leaving such big structures...
thanks all of u experts for your suggestion and hlp...

12

General Questions and Answers / Re: how to solve optamization problem in vnl?

« on: October 4, 2016, 08:02 »

thank you sir, i got it..
but in this type( below attached) of error, how can i proceed??

       THANK YOU IN ADVANCE...

13

General Questions and Answers / Re: K-poit selection

« on: October 3, 2016, 07:51 »

yes, absolutely mr.  Daniele Stradi. i also try BS Dos and total energy vs. changing k points with remainng all parameter same.. it shows variation in result. nature of material also changes as band structure...

14

General Questions and Answers / Re: how to solve optamization problem in vnl?

« on: October 3, 2016, 07:41 »

sorry, i cant understand, can u plz elaborate..
you mean here in calculator? i set the linear threshold to '0' and in geometry optimisation
the value for the stress and force is leave defult.. how can i lower the threshold below 0??
thank you sir fore ur response and hope u will again..  

15

General Questions and Answers / how to solve optamization problem in vnl?

« on: October 2, 2016, 19:25 »

Dear Quantum-wise staffs,
 
                                       i'm trying to optimise TiC nanotube of (14,14) armchair structure but could not success  and shows the error as mentioned below  attached file. plz help me how to solve this problem to optimise it? what is problem in Vnl behind it?