I was just told,but I will test it some time. Thanks very much. Dexi Shao
2014-07-21 18:06 GMT+08:00 Максим Арсентьев <ars21031...@gmail.com>: > It's surprising, are you sure? > > > 2014-07-21 13:48 GMT+04:00 邵德喜 <dxshao...@gmail.com>: > > I was told that when MD.VariableCell is setted True, then we can not >> use block kgrid_Monkhorst_Pack option . >> Thanks very much . >> >> >> 2014-07-21 15:31 GMT+08:00 Максим Арсентьев <ars21031...@gmail.com>: >> >> You right, you should perform 2 structural relaxations. Before doing this >>> do calculations without geom. optim. with different density of kpoints by >>> "%block kgrid_Monkhorst_Pack" and see convergence of kpoint density on >>> forces. This also should be checked for meshcutoff - convergence in forces >>> is very important for geom. optim. >>> >>> >>> 2014-07-21 6:59 GMT+04:00 邵德喜 <dxshao...@gmail.com>: >>> >>> Thanks very much. >>>> Do you mean that I should do structual relaxation twice?First with >>>> MD.VariableCell >>>> False,then with MD.VariableCell True? >>>> If I could just do structual relaxation once with MD.VariableCell >>>> True? And if " kgrid Monkhorst Pack" option can be reserved at the >>>> same time? >>>> Yours Sincerely! >>>> Dexishao >>>> >>>> >>>> 2014-07-21 4:55 GMT+08:00 Максим Арсентьев <ars21031...@gmail.com>: >>>> >>>> Dear, Dexi! >>>>> >>>>> You can vary residual strain by MD.MaxStressTol. >>>>> Use CG, relax with MD.VariableCell False first, then input >>>>> coordinates obtained to a new file with MD.VariableCell True. >>>>> Note you may need to shift some atoms manually before geometry >>>>> optimization: if all atoms are in 2D plane, then all of them will remain >>>>> in >>>>> plane after geom. optim. because z forces are zero, so you need to shift >>>>> any atom to unlock z forces and avoid such a false state. >>>>> >>>>> >>>>> 2014-07-20 4:01 GMT+04:00 邵德喜 <dxshao...@gmail.com>: >>>>> >>>>> Dear everyone: >>>>>> I really want to know how to get a structure wuthout strain.For >>>>>> example ,Let's consider graphene ,I get the structure from materials >>>>>> studio,and use it as initial one for siesta structual relaxation. >>>>>> If in the relaxation set some options as follows: >>>>>> MD.TypeOfRun CG/Verlet >>>>>> MD.VariableCell True >>>>>> ... >>>>>> At the same time ,I replace " kgrid Monkhorst Pack" option with >>>>>> k-grid cutoff. >>>>>> When the relaxation is done,I want to ask if the final structure >>>>>> after relaxation is >>>>>> one structure without strain? >>>>>> In general ,how to get a structure without strain is what I care. >>>>>> Thanks in advance. >>>>>> Dexi Shao >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> 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 >
