I will let the MD experts to reply to this question :) On Sat, Aug 6, 2016 at 2:49 AM, Narendranath Ghosh <ghosh.nare...@gmail.com> wrote:
> Dear Dario > > Thank you very much for your valuable suggestion. As my systems are quite > large and require high computational resources , I decided to compare one > of my result with that of PBE0. > > One problem that I am facing now "after successfully optimized the > (CNT+Fullerene) systems now I am looking for to get 5 picosecond "md" > trajectory". > In QE which flags allowed one to get *MD trajectories * *with NVE > ensemble. *I find some idea from http://qe-forge.org/piper > mail/pw_forum/2009-June/087573.html. But that is not clear to me. > > Please suggest any idea..... > > Thank you again > > *Narendra Nath Ghosh* > > *Research Associate* > > *University of Gour Banga* > > *Department of Computational Physics * > > *Malda-732102* > > *India* > > On Sat, Aug 6, 2016 at 10:48 AM, dario rocca <roc...@gmail.com> wrote: > >> Dear Narendra, >> If you do a PBE calculation with norm-conserving, ultrasoft, and PAW >> pseudopotentials very likely you will get very similar results (but it >> depends >> also on the quality of the pseudopotential, the property under >> consideration, etc.). >> In the case of PBE0 the type of pseudopotential will have a stronger >> effect on the final result. >> For purely esthetic reasons, if your previous calculations didn't take >> too long you could redo them with norm-conserving pseudopotentials and >> confirm that the results are indeed the same. >> Otherwise I don't see anything wrong in comparing, for example, a gap >> obtained at PBE level with US pseudos and a gap obtained at PBE0 >> level with NC pseudos. >> Best, >> Dario >> >> >> >> On Fri, Aug 5, 2016 at 3:44 PM, Narendranath Ghosh < >> ghosh.nare...@gmail.com> wrote: >> >>> Dear Dario >>> >>> Thank you very much for your support.It works well and some of the >>> jobs have been finished successfully. >>> >>> But one thing in my mind. In my whole calculations , I used PBE with >>> ultrasoft pseudopotentials. But to do "scf" calculations with PBE0 "hybrid" >>> functional I have to use "Norm conserving pseudopotential". So how can >>> I compare these two results. >>> >>> Please suggest any idea..... >>> >>> Thank you again >>> >>> *Narendra Nath Ghosh* >>> >>> *Research Associate* >>> >>> *University of Gour Banga* >>> >>> *Department of Computational Physics * >>> >>> *Malda-732102* >>> >>> *India* >>> >>> >>> On Thu, Aug 4, 2016 at 2:17 AM, dario rocca <roc...@gmail.com> wrote: >>> >>>> Dear Narendranath, >>>> Your calculation has reached convergence if you read the message "EXX >>>> self-consistency reached". >>>> You can learn some details about the scf procedure with hybrid >>>> functionals in PW/examples/EXX_example. >>>> PBE0 and hybrid functional calculations are in general very expensive. >>>> I would suggest you run an example to see what to expect. >>>> You might also try to perform a calculation on your system with minimal >>>> computational parameters (very small cut-off, few/one k-points) just to see >>>> that your run can indeed terminate smoothly. Then I would look for a set of >>>> parameters which are a good compromise between computational time and the >>>> accuracy you need. >>>> You might also try to modify the parameter ecutfock to gain some speed. >>>> For sure a hybrid functional calculation on a CNT+Fullerene system >>>> might be rather challenging. >>>> Best, >>>> Dario >>>> >>>> On Wed, Aug 3, 2016 at 11:16 AM, Narendranath Ghosh < >>>> ghosh.nare...@gmail.com> wrote: >>>> >>>>> Dear all >>>>> >>>>> After optimizing a system "CNT+Fullerene" with >>>>> "PBE" I am trying to calculate "scf" calculation with "PBE0" hybrid >>>>> functional using NC Pseudopotential. >>>>> >>>>> In output file I found "*convergence has been achieved in 15 >>>>> iterations" *But the job was not finished even after more than one >>>>> week. I could not find any mistake in my input. >>>>> >>>>> >>>>> Please suggest any idea. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Pw_forum mailing list >>>>> Pw_forum@pwscf.org >>>>> http://pwscf.org/mailman/listinfo/pw_forum >>>>> >>>> >>>> >>>> _______________________________________________ >>>> Pw_forum mailing list >>>> Pw_forum@pwscf.org >>>> http://pwscf.org/mailman/listinfo/pw_forum >>>> >>> >>> >>> _______________________________________________ >>> Pw_forum mailing list >>> Pw_forum@pwscf.org >>> http://pwscf.org/mailman/listinfo/pw_forum >>> >> >> >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum@pwscf.org >> http://pwscf.org/mailman/listinfo/pw_forum >> > > > _______________________________________________ > Pw_forum mailing list > Pw_forum@pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum >
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