States for CDFT-CI

How does one select and specify the N states one wishes to include in a CDFT-CI? Neither the manual ot the forum offers any insight.

What are you trying to accomplish? For this method, CDFT is used to obtain physically-relevant diabatic states but what is physically relevant really depends on what you are trying to do.

I’m pulling apart an oligomer of DNA at the point experimentalists believe is a starting point for a chromosomal translocation process. In doing this, I am breaking several P-O bonds and I need to get the correct electronic representation along the path of the separation up to complete dissociation.

Unrestricted DFT is a good start but it does not provide a clean representation for this case of strong correlation that needs to be addressed.