[Re:03] problem of natmmx

Posted on : May 21, 2016 (Sat) 16:52:01

by Administrator

Dear Mouna,

ncmpmx is the maximum number of components that system contains. For example, if it is bcc Fe_1-x Co_x random alloys, the number of atoms in the primitive unit-cell is 1 but the number of the component atoms is 2 (Fe and Co). Then for such calculation natmmx=1 and ncmpmx=2 is the required minimum size. Larger is not the problem. msizmx is the maximum size required for the Green\'s function. Suppose that you have N atoms in the unit cell. For each atom, calculate m=(l_max+1)^2. Here l_max is the angular momentum you take into account. Normally l_max=2 (include up to d-scattering) or 3 (include up to f-scattering). Then some over m for all those atoms in the unit cell. The result gives the minimum size you need to perform the calculation. Therefore, if it is bcc Fe and you take up to d-scattering, msizmx=9. If it is hcp Co, msizmx=18.