How to implement the function of yambo_surf?

[Conor Hogan]

Dear Chenhai,
Unfortunately as you said, the yambo_surf has not been ported to version 4+ of Yambo. I will do it this year but as it is a rarely requested feature it is somewhat low priority.
In the meantime my advice is to use the normal yambo to compute the epsilon of the cell for q along the two perpendicular surface axes and calculate the RAS yourself. You therefore need to use a symmetric slab. This is the process you would follow if you wanted to compute RAS with GW-BSE, for instance. Similarly you could compute the HREELS but it's a bit more difficult. If you cannot make a symmetric slab for some physical reason and need to use the real space cut off, I"m afraid the only possibility for now is to use v3.4.
Best regards,
Conor