Dear Yingli Niu, I do not have a straightforward answer - it depends also a lot on what you want the el-ph for, or why.
My inclination would be this - for any given phonon, the electron-phonon coupling is given by an integration over the BZ (see e.g. Mauri 1996 PRL, Eq 2). So, you can always select, one at a time, surface phonons that interest you. Then, it's less clear what to do. You could e.g. calculate the max-loc Wannier functions for the system, and then use only the ones that sit on the surface to construct, via Bloch sums, the u_nk's (i.e. the periodic part of the Bloch orbitals) that go in Eq. 2 above. Or you could directly transform the integral of Eq 2 into a max-loc representation, then keep only stuff that is on the surface of the slab. It's not terribly complicate, but if you are a newcomer to the field, it requires a lot of homework with the codes. Both Feliciano Giustino and Ivo Souza, in Berkeley, might be working at related projects. nicola ?? ? wrote: > Prof Nicola, > Thank you! Thank you very much!!! > And thanks a lot for Dr.Claudia Bungaro's PhD paper. > Now I kown how to insert the bulk constants in to > the slab. > One more question, I want to calculate the el-ph > interaction of a metal surface next step. If I use a > normal method in pwscf, I will get interaction between > all phonons(surface+resonance+bulk) and all > electrons(surface+resonance+bulk).If I want to analyse > the el-ph interaction at surface, should I selected > the surface phonons and surface electrons out? Does it > means that I should modify the pwscf source files? May > I specify the phonon mode of some special q point, > then calculate the lamda(q,v) with the surface > electrons? > Are there any articles about these? > Thanks > Best regards > > Yingli Niu -- --------------------------------------------------------------------- Prof Nicola Marzari Department of Materials Science and Engineering 13-5066 MIT 77 Massachusetts Avenue Cambridge MA 02139-4307 USA tel 617.4522758 fax 2586534 marzari at mit.edu http://quasiamore.mit.edu
