Dear Madhura, > 1. While calculating STM image, is sum taken over both the spin > channels? Because there is no option for spin resolved calculations, > and in the subroutine I was not able to find where sum is done.?
Yes it is. The sum is taken over all k-points, regardless of the spin this kpoint correspond to (as you know, in pwscf spin "up" and spin "down" are treated as two sets of kpoints). > 2. Does anyone have a subroutine to get spin-polarized STM image? If > yes, can you send it? You might consider using again pp.x to plot the ILDOS in the corresponding energy range, for which you can specify the spin component. Although the weight of states contributing to ILDOS and STM is not computed exactly in the same way by pp.x, you should expect the results to become equivalent as the number of relevant states falling in the energy interval is sufficiently large (see, number of kpoints & slab thickness). > 3. Or if not, can anyone tell which part of code needs to be modified > to get SP-STM image? At line 150 of PP/stm.f90, "DO ik = 1, nks". You could restrict this summation to states with wanted spin, or accumulate the two sums independently. The spin of each kpoint is stored in isk(ik). See its use in projwfc.f90 for examples. HTH -- Guido Fratesi Dipartimento di Scienza dei Materiali Universita` degli Studi di Milano-Bicocca via Cozzi 53, 20125 Milano, Italy
