It's in French. Best wishes, Maxim.
2014-07-26 17:36 GMT+04:00 邵德喜 <dxshao...@gmail.com>: > Thanks very much.Is it Spanish? I can't understant it ,but I 'll try my > best to catch it . > Dexi Shao > > > 2014-07-26 21:24 GMT+08:00 Максим Арсентьев <ars21031...@gmail.com>: > > more easily to take only max force for plot from output. See pages 79-80 >> of file attached - it can help you to choose these parameters >> >> >> 2014-07-26 17:18 GMT+04:00 Максим Арсентьев <ars21031...@gmail.com>: >> >> it is *.FA file contains forces (eV/Ang) >>> >>> Best wishe, Maxim. >>> >>> >>> 2014-07-26 17:00 GMT+04:00 邵德喜 <dxshao...@gmail.com>: >>> >>> Dear Maxim: >>>> I'm so sorry to disturb you again,but I've completed the kpoint grid >>>> convergence with a reletive high value of Meshcutoff just follow your >>>> words.Then I've got many FORCE_STRESS files related to different kpoint >>>> grid.In these files the first four lines is just as follows： >>>> -1470.4169519132 >>>> -0.000001407 -0.000000013 0.000000004 >>>> -0.000000013 0.000000460 0.000000004 >>>> 0.000000004 0.000000004 0.000050126 >>>> I want to know what does the first line "-1470.4169519132" mean?And >>>> you've told me the parameter used to convergence test is Force.Is Force >>>> you mean the value " -1470.4169519132" or the next 3*3 matrix >>>> -0.000001407 -0.000000013 0.000000004 >>>> -0.000000013 0.000000460 0.000000004 >>>> 0.000000004 0.000000004 0.000050126 >>>> ? >>>> Thans very very much . >>>> Dexi Shao >>>> >>>> >>>> 2014-07-25 20:39 GMT+08:00 邵德喜 <dxshao...@gmail.com>: >>>> >>>> Thanks very very much for all your replay,saluted all of you ! >>>>> Dexi Shao >>>>> >>>>> >>>>> 2014-07-25 19:22 GMT+08:00 Максим Арсентьев <ars21031...@gmail.com>: >>>>> >>>>> Yes, you right. >>>>>> To clarify 1st keep fixed high meshcutoff and vary kpoint -> select >>>>>> kpoint and keep it fixed but vary meshcutoff >>>>>> Maybe this can be vice versa, or not,but possibly it is not so >>>>>> important (final value of meshcutoff about 350-400 Ry, sometimes for late >>>>>> heavy transition metal elements, with oxygen maybe it can be more) >>>>>> >>>>>> >>>>>> 2014-07-25 5:53 GMT+04:00 邵德喜 <dxshao...@gmail.com>: >>>>>> >>>>>> I see.You mean that I should set CG steps as usual as we do >>>>>>> structual relaxation(foer example :500) during all the convergence >>>>>>> tests . >>>>>>> And consider kpoint grid convergence first with a reletive high >>>>>>> value of Meshcutoff.When it is done ,plot how it depends on FORCES >>>>>>> from >>>>>>> the output file in the final convergency step .Then consider meshcutoff >>>>>>> convergence test with the convergency kpoint grid. >>>>>>> When the convergence tests is completed ,structual relaxation is >>>>>>> also completed,so I do not need to do structual relaxation additionally. >>>>>>> Is it all right? >>>>>>> Thanks for all your replay! >>>>>>> ( PS: I‘m so sorry but the service is just out of work.I'll upload >>>>>>> my input fdf file as soon as it recovers.) >>>>>>> Dexi Shao >>>>>>> >>>>>>> >>>>>>> 2014-07-25 1:14 GMT+08:00 Максим Арсентьев <ars21031...@gmail.com>: >>>>>>> >>>>>>> Dear Dexi! >>>>>>>> >>>>>>>> You should not set nember of CG steps to zero - it is not >>>>>>>> necessary. You right that you should perform convergence of your >>>>>>>> property >>>>>>>> of interest, but first structural relaxation is important as I suppose >>>>>>>> - >>>>>>>> maybe not in your case, but often it is so. So select high meshcutoff >>>>>>>> about >>>>>>>> 400-500 and vary density of kpoint grid and plot how it depends on >>>>>>>> FORCES. >>>>>>>> From this plot you will select kpoints, then take this kpoints fixed >>>>>>>> and >>>>>>>> vary meshcutoff to plot dependence on forces again. It is forces, not >>>>>>>> total >>>>>>>> energy are relevant for structural relaxation. Enter in google >>>>>>>> "graphene >>>>>>>> transiesta" and 1st link will help I believe. >>>>>>>> >>>>>>>> четверг, 24 июля 2014 г. пользователь 邵德喜 написал: >>>>>>>> >>>>>>>> Thanks very much.The unit is Ry. >>>>>>>>> I was told that when I get the original structure ,I should do >>>>>>>>> convergence tests first,structual relaxation comes second. >>>>>>>>> In my opinion ,do convergence test without structual relaxation I >>>>>>>>> should set CG step to zero. >>>>>>>>> problem1:I check the convergency (in terms of gradually increase >>>>>>>>> Meshcutoff) of the total energy may be useless >>>>>>>>> because I was told "we should check the convergence not of the >>>>>>>>> total energy but of those properties which are relevant for our study >>>>>>>>> in >>>>>>>>> question ". >>>>>>>>> But I just want to study the current-voltage relation ,it's >>>>>>>>> expensive for me to check the convergence of its transport property. >>>>>>>>> So I check the convergence of total energy instead o >>>>>>>>> pportunisticly. >>>>>>>>> The input.fdf file is as follows. >>>>>>>>> Thans for your replay. >>>>>>>>> Dexi Shao >>>>>>>>> >>>>>>>>> >>>>>>>>> 2014-07-24 18:22 GMT+08:00 Kanhao Xue <xuekan...@gmail.com>: >>>>>>>>> >>>>>>>>>> Dear Dexi, >>>>>>>>>> >>>>>>>>>> I wonder what is the unit of your Mesh cutoff? Is it in Ry? >>>>>>>>>> >>>>>>>>>> Siesta is using atomic orbital as the basis, which is quite >>>>>>>>>> different from plane-wave based codes like VASP. In plane-wave code, >>>>>>>>>> the >>>>>>>>>> plane wave cutoff energy directly determines your basis, and thus >>>>>>>>>> influences the result a lot. >>>>>>>>>> >>>>>>>>>> In Siesta we have the mesh cutoff concept. A large cutoff is >>>>>>>>>> required for accurate result. Usually for LDA, 250 Ry is sufficient >>>>>>>>>> and for >>>>>>>>>> GGA 350 Ry is sufficient. >>>>>>>>>> >>>>>>>>>> In my opinion you do not need to go up to 600 Ry to check. >>>>>>>>>> >>>>>>>>>> However, indeed your energy changes too much with Mesh cutoff. >>>>>>>>>> Can you upload your input fdf file for more information? >>>>>>>>>> >>>>>>>>>> Kanhao >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Thu, Jul 24, 2014 at 11:43 AM, 邵德喜 <dxshao...@gmail.com> >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Dear everyone: >>>>>>>>>>> I have done the convergence test when I check the convergency >>>>>>>>>>> (in terms of gradually increase Meshcutoff) of the total energy, I >>>>>>>>>>> found >>>>>>>>>>> that the Total energy rise up when I increase the parameter of >>>>>>>>>>> Meshcutoff >>>>>>>>>>> (please refer to the accesory) .Is it reasonable? >>>>>>>>>>> Ahy replay will be appreciated. >>>>>>>>>>> Dexi Shao >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> >>>>>>>>>> Sincerely yours, >>>>>>>>>> Kanhao Xue >>>>>>>>>> >>>>>>>>>> Laboratoire de Réactivité et Chimie des Solides (LRCS) >>>>>>>>>> UMR CNRS 7314 >>>>>>>>>> Université de Picardie Jules Verne >>>>>>>>>> 33 Rue Saint Leu, 80039 Amiens Cedex, France >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Best wishes, >>>>>>>> Maxim Arsent'ev, D.Sc.(Chemistry) >>>>>>>> Laboratory of research of nanostructures >>>>>>>> Institute of Silicate Chemistry of RAS >>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Best wishes, >>>>>> Maxim Arsent'ev, D.Sc.(Chemistry) >>>>>> Laboratory of research of nanostructures >>>>>> Institute of Silicate Chemistry of RAS >>>>>> >>>>> >>>>> >>>> >>> >>> >>> -- >>> Best wishes, >>> Maxim Arsent'ev, D.Sc.(Chemistry) >>> Laboratory of research of nanostructures >>> Institute of Silicate Chemistry of RAS >>> >> >> >> >> -- >> Best wishes, >> Maxim Arsent'ev, D.Sc.(Chemistry) >> Laboratory of research of nanostructures >> Institute of Silicate Chemistry of RAS >> > > -- Best wishes, Maxim Arsent'ev, D.Sc.(Chemistry) Laboratory of research of nanostructures Institute of Silicate Chemistry of RAS
