Dear David, If your structure is 2D and with some vacuum let say along Z, then you may be looking for bands in the XY plane which you have periodicity. So your automatic k-points should be look like: (kx ky 1) and for band structure you need to use manual k-vectors and span the XY plane along high symmetry points (more points, finer bands).
And for the bands you got for the vacuum region I have no idea unless you attach your inputs as well. Best, Hadi. -----Original Message----- From: pw_forum-bounces at pwscf.org [mailto:[email protected]] On Behalf Of David Foster Sent: 09 March 2014 19:19 To: pw_forum at pwscf.org Subject: [Pw_forum] choosing k-point in slab calculations Dear Users Suppose, we have constructed a metallic surface and a vacuum slab with some thickness. Normally, these super-cells have no symmetry. My main question is that how we should choose the k-point? Only in the surface or we can choose some points in the inner layers or even vacuum near to the surface? PS: I have calculated band structure for the plane parallel to the surface but in the middle point of the vacuum (far from the surface). I expected that I didn't get any band graphs; however, I got some. Can anybody tell me why? Regards David Foster Ph.D. Student of Chemistry _______________________________________________ Pw_forum mailing list Pw_forum at pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
