I could finish a test case. I need to define some variables in qe.in file. Will get back to you once I finish it.
Thank you sir, best wishes Rekha On Sat, Jan 4, 2020 at 2:08 PM rekha sharma <[email protected]> wrote: > Dear Sir, > Thanks for your reply. > It is very useful for me. > Consider my apology for late reply as my computer was not free. > > ecutrho 52 is by mistake. actually it is 520 (uspp). > > I tried to run calculations for "V" but I could not finish pp.x. > I run pw.x followed by pp.x. > > my pp.in is > > &inputPP > prefix = 'pwscf' > outdir='/tmp-$i', > plot_num=11 > filplot = 'pp-$i.pot' > / > > &plot > iflag=3, > output_format=5 > / > > where prefix and outdir is same as I used in in my scf file. > > I am getting below xml error > > Error in routine pw_readschemafile (1): > xml data file not found > > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > > stopping ... > > > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > Error in routine pw_readschemafile (1): > xml data file not found > > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > > stopping .. > > Please suggest me how to run pp.x. > > My problem is related with this issue > <https://lists.quantum-espresso.org/pipermail/users/2017-November/039771.html> > but I am not doing any restart_mode calculation. > > > Best Wishes, > > Rekha > > > > On Thu, Jan 2, 2020 at 6:50 PM Lucas Nicolás Lodeiro Moraga < > [email protected]> wrote: > >> Hello Rekha! >> I am not an expert in monolayers, I work with slabs, but the problems >> should be similar. >> First, the ecutrho value that you use (52) it is very low... I do not >> know wich type of pseudopotential do you use (NormConserving, UltraSoft, >> PAW), but the ecutrho must be 4 times the ecutwfc (For US and PAW form 6 to >> 12 times). Other thing, the convergence criteria of 1meV its good, but I >> prefer a criteria independent of number of atoms, as 1meV/atom... If you >> have the same system with more atoms, with your criteria you need a higher >> values to reach ir, but if use an independent atoms criteria, the values >> are the same for small and big systems. >> >> MONOLAYER: >> kpoints: I use 1 point in the vacuum direction, and I do not found any >> difference when I use 2 or more kpoints in this direction. The bands >> dispersion in this direction is negligible. >> cell: The 2Dshape flag does not change your cell because it does not >> change the xy area, how you have an orthogonal a,b vectors and a=b. The >> broken of this symmetry is energetically not allowed. For this, 2Dxy flag >> works and minimize the cell in xy directions, and reduce the stress. >> If is it okay the parameters deviates from the bulk? I do not know for >> the case of Monolayers... but for me makes sense, in your calculation the >> xy area reduces to maximize the interaction with the neighborhood. If you >> want do a vc-relax the 2Dxy is the correct flag. >> Vacuum: 30 bohr should be enough... In my systems I do a similar vacuum >> test, and 30 bohr gives the same result as 200 bohr. >> I guess your system have charged surfaces, dipoles or something like >> that. If is a bynary semiconductor AB... a monolayer gives you a "A type" >> and a "B Type" surfaces, how A and B have different electronegativities, >> exists a dipole between both surfaces, that could explain the energy >> behaviour with vacuum. >> I recommend, do a post-processing calculation for the monolayer, >> calculate the electrostatic potential (V) along the vacuum direction... If >> V is not plane in the vaccum region, do you have a dipole on the monolayer. >> You can fix it using a dip-field on the vacuum... with it you add a "V >> step" on the vacuum, giving you two V planes on vaccum, "two types of >> vaccum". >> Other way, is making a monolayer with equal surfaces, like A-A or B-B >> (adding a plane of atoms)... this fix the dipole in most cases... but I do >> not know if this is still a monolayer or what you want. >> >> Regards >> >> Lucas Lodeiro >> >> > > -- > > > > > Best wishes > > Ms. Rekha > Ex-PG student, > LBS college, Jaipur > India > Mob.: +11 90-95 790 71 697 > Email: [email protected] > -- Best wishes Ms. Rekha Ex-PG student, LBS college, Jaipur India Mob.: +11 90-95 790 71 697 Email: [email protected]
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