c_propene
Kimball's cyclo-propene with Pauli excluded overlap region.
This is caused by Kimball spheres centered on each C-C
bond direction. If the clouds are allowed to yield away from the
bond direction, no (or very small) overlap and exchange
corrections are necessary, see cyclo-propane below:


This is a computation with eFF.exe from Su and Goddard III see here.

with eFF