thanks a lot
On Sat, Jan 25, 2014 at 2:50 AM, Abraham Hmiel <[email protected]> wrote: > Suman, > > I think the answer you're looking for is 42. Only 42-atom simulations are > considered by peer review ;) > > But joking aside, you should look to previously-published ab-initio > results in your system of interest or something close to it. Even if such > results exist, you should perform methodological checks on system size, > i.e. size-convergence simulations with respect to: the number of layers in > a surface slab, or supercell dimensions if you're simulating a bulk > compound (perhaps with a defect or other non-homogeneity), different sizes > of nanowire, etc. Some of the most important current problems in > nanoscience involve quantum size-effects, and you don't really know how > many atoms a "good" simulation requires until you try it- the physics of a > particular solid-state system can vary dramatically based on small size > increments! > > So, to answer the question you posed, no real "number of atoms" guideline > exists. Use what is feasible and timely for your computational setup while > giving trustworthy, meaningful, repeatable results! By the way, the "T" in > siesta stands for "Thousands" (but this only really makes sense with the > order-N functional). The number of atoms in a SIESTA simulation could be > anywhere in the range {10^0, 10^4}. > > -- > *Abraham Hmiel* > Katherine Belz Groves Fellow in Nanoscience > Xue Group, SUNY College of Nanoscale Science and Engineering > http://abehmiel.net/about > > On Fri, Jan 24, 2014 at 8:21 AM, Suman Chowdhury < > [email protected]> wrote: > >> Dear all, >> what is the typical number of atoms one should use for publishable >> results using SIESTA? >> > > > >
