This observation is consistent with physical intuition regarding antiferromagnetic interactions in multimetallic molecules. Recall that we are attempting to explain why the low-spin LASSI [1,q] energy converges at different rates in the different active spaces. In low-spin states of molecules such as this, the unpaired electrons occupying the singly-occupied orbitals, become antiferromagnetically coupled. If this process is to be described with model states in which electrons hop from one fragment to another, it follows intuitively that they should be hopping out of and into the singly-occupied orbitals on each fragment. In the smaller active space, this happens because the only alternative is to donate the electron out of the core-hybridized a orbital, which has an extreme energy penalty. But in the larger active space, lower-ϵ n model states are accessible and are preferentially obtained, and these make poorer models of antiferromagnetic interaction.