Hi, and sorry for the late answer; it's easier to reach me using email since I only seldom look at these forums. So, I understood that you need to relate the inner shell electrons (ab initio/MPQC) to the atoms. Perhaps drawing a plot for these MO's can be used for this; the plots should be local and you can then see in which atoms does it relate. I don't know any easier way, neither in the GUI nor in the MPQC code. Regards, Tommi