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Chlorophyll mediates a photochemical reaction: energy from a visible light photon is used to reduce CO2 to CHO, and the energy from that photon can later be recovered when CHO is oxidized back to CO2 in an organism.

Is there any analogous photochemical reaction where energy from shorter wavelength ionizing radiation (like Xrays or gamma rays) is captured in a molecule such that it can later be recovered chemically to do work? I do not think any biochemistry happens along these lines but maybe synthetic corroles or porphyrins have been made that can accomplish this.

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    $\begingroup$ There is a field called betavoltaics, analogous to photovoltaics. However, my understanding is that organic materials would perform poorly in betavoltaic cells due to radiation damage. $\endgroup$ – Nicolau Saker Neto Jan 2 at 21:56
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    $\begingroup$ The major effect x-rays have is to cause many energetic electrons to be produced from the solvent that then cascade down in energy ionising all in their path. It is a major headache in the x-ray crystallography of proteins. $\endgroup$ – porphyrin Jan 3 at 14:07
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    $\begingroup$ IF the radiation is ionising it is usually too energetic to be useful for any chemical process. But near UV through to IR might, in principle and in some cases, be capturable by some chemical process. $\endgroup$ – matt_black Jan 3 at 14:35
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The energy scales of x-ray and gamma radiation are too large to be chemically helpful in the way that the electromagnetic around visible wavelengths is.

X-rays, if absorbed, typically excite core electrons of atoms. As we know, core electrons are (to a first approximation) not affected by the details of chemical bonding in the valence, so any attempt to use a chemical bonding motif to capture x-rays (e.g. conjugation of porphyrins) is of the wrong energy scale. You could use the Auger Effect to eject a valence electron with x-ray scale energy. This does constitute radiationless conversion of the light into electronic energy, but it doesn't meet your qualifications for storing and extracting work.

Gamma rays are typically produced by the decay of one nuclear state to another, and are vastly different in energy scale than electronic states, so there's no way to do chemistry with gamma radiation, at least directly. The Mössbauer effect does allow us to use gamma rays to understand local structure in a crystal, but even then most of the energy is absorbed into exciting the nuclear state, which we cannot control chemically.

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