Negative contribution in RAS-SF wavefunction decomposition

Dear Q-Chem community,

I am running RAS-SF calculations to see the wavefunction decomposition.
There are some questions.

The output file gives me the negative contribution of dimer SS exciton like below.

Dimer Excitons (DE)
SS TT Total
-.3717 0.4056 0.0339

How is it possible and how to interpret this result?

What does “ME” stand for in local excitons information?
It is like double excitations from HOMO to LUMO within the chromophore A?
Please refer to the results shown below.

Local Excitons (LE)
A B Total
SE 0.0000 0.0000 0.0000
ME 0.5031 0.0000 0.5031

Any comments will be highly appreciated.


ME is probably “multi-exciton”, meaning doubles as you suggest. Not sure about the negative contribution, doesn’t seem to be any sample job.