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Chemistry on inner domain only

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Is it possible to run multiple nested domains (on line one way nesting, not ndown) with the chemistry enabled ONLY in the inner domain?

If so, can someone explain how?

So far I have my emissions for the inner domain generated with no problems using prep_chem_sources + convert_emiss for the inner domain. I change the namelist.input to include all the domains + chemistry activated only in the inner domain. Real.exe runs without complaining. But when I try to run wrf, it tries to open emission files for the coarser domain.
As far as I'm aware you need the same chemical scheme in all domains - so that you have the same variables in each domain (so that nesting works properly).

Even if it was possible, I don't think that it would be worthwhile running nested domains with only chemistry in the inner domain. If you are unconcerned about accuracy of the chemical simulations on the outer domain I would, instead, set the chemistry (and other) timesteps to be longer, so that less compute time is spent on the chemistry in those domains.