[GrimTheCat]

In the picture I have included, there are 3 orbitals. Orbital A and B are parallel with each other. Orbital C is perpendicular to them, but only "interacting" with the bottom parts of orbitals A and B. Is it possible for there to be a bonding interaction between orbitals A and B? If so, is the bond considered a sigma bond?

[GrimTheCat]

With more thought I think I have answered my own question. As long as there is enough overlap in the shaded part of the orbital, then a bond is possible. Since it's is just with one lobe, then it is a sigma bond.

I don't think that orbitals A and B can be parallel, they probably have to be angled towards each other.

[Corribus]

Orbital interactions don't really work like this. And It's hard to imagine what kind of molecule this would take place in,  anyway.

[GrimTheCat]

Orbital interactions don't really work like this. And It's hard to imagine what kind of molecule this would take place in,  anyway.

The example is decidedly not a good one, but it enabled me to think critically about the real system I'm looking at.

If you're curious: I am looking at the electronic density of a LUMO, and seeing a bond with only part of the orbital. In other similar molecules there is conjugation in the ring system. However, only half of the molecule looked like it was conjugated in that particular LUMO and I need to be able to explain what is happening.

I included a very crude picture if the above paragraph is unclear. Although now I'm wondering if it'll make things more unclear. ¯\_(ツ)_/¯

[Corribus]

 Can you be more specific about "other similar molecules"?

[GrimTheCat]

They are BODIPYs with S,N,O-R,R' groups and halogens in certain positions on the core.