I am trying to run an exciation energy calculation for a lithium atom. Is there a way to force the initial HF calculation to follow a specific excited state configuration, i.e. to skip or leave some shells empty?
For example, I want to compute the energy of the state "1s2 3s1" so 2s orbital is skipped, but I received an error message:
OCC input inconsistent with ms2
My input section looks like: