I think the proposal here is more, "why can't we use something like this?" and then add the properties that we need via invoking handwavium, rather than "let's use this literally as it exists in the source material." So let's think about this... A nanopartical "gas", but it kind of binds itself together in a way that keeps it from floating off into space. It acts like a barrier to other gasses, but doesn't impede anything else. Maybe a tuned force field effect for both of these properties? Essentially giving the atmosphere a "surface tension" that holds gasses in. (And which you can surf on.) Once you have that, making it greenhouse and UV-screen would be trivial. I don't think oxygenation would be a good function for it, but that can be handled by some other device. Once you have a lid on the atmosphere, the oxygen is less troublesome.
-- Bob
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Then the horns kicked in...
...and my shoes began to squeak.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.