What would need to happen in order to make a compound with neon and helium? We know it's impossible, but super hypothetically if we could do magic and fuse them together, how would that look like? Would a determined number of electrons have to go away? Would the van der Waals forces need to be weaker?
I'm trying to find visual ideas for a romantic fusion of two entities: Neon and Helium. I want to get as close to reality as possible (a molecule, not an atom). Since it isn't an actual possibility, I want to just to see if can get inspired with whatever gets the closest and get a sci-fi visual idea. Something that comes to mind is having them both be squeezed by two diamonds. I would appreciate getting better answers, even if they are sci-fi impossibilities.
High pressure, high heat electrical chamber of compressed gas.
Using electrical pulses you can make dimers of hydrogen and helium. Perhaps your magic has a way to stabilize this, and by making a very high pressure compressed by diamonds chamber with electrical sparks running through you can stabilize a hydrogen helium dimer with high energy electrons.
An area of space that changes the math of electron shells
The reason Neon and Helium don't bond is because all of their electron orbitals are filled. The math of the electron orbitals comes from solutions to the Schrödinger equation (a partial differential equation) which correspond to different amounts of energy and the number of electrons that can occupy those states.
If there was a place that changed the conditions under which that differential equation was solved, then it's possible that there might be additional orbitals available at the energy levels of the electrons in helium and neon (and probably every other element in the field), but this would mean that now your helium and neon would like to share electrons in order to fill these new orbitals that only exist in your field/special area of space.
The result will still have the same number of electrons to balance the number of protons. The electrons would need to be flowing between the two atoms. That means that the top electrons are not as tightly bound to those orbitals. That might make for a gas that easily shines. Add some static electricity and it glows. It also might be a highly reactive gas simply needing another atom to merge with.