Dear Siesta users, I have always simulated bulk materials with periodic boundary conditions. Now I have to simulate a material that is not anymore infinite in at least one direction and that is thus terminated by a surface in such direction. For example I want the material to be infinite in +x,-x,+y,-y and -z but have the +z direction terminated by a surface. I can thus apply periodic boundary conditions in all directions but not in the one of the surface +z, and -z as a consequence. How can I have the material infinite in -z direction but finite in +z? Neither in the manual nor in the discussions of the forum I have found any indication on this. Thanks very much in advance,
L.
