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In common glowsticks, diphenyl oxalate reacts with hydrogen peroxide, forming 1,2-dioxetanedione. The dioxetanedione is unstable, but direct decomposition to carbon dioxide is a forbidden transition, so this can only happen in a reaction with another molecule. If the other molecule is a suitable fluophore dye, the dye molecule will become exited and then emit a photon of light. (The color depending on the fluophore used.)

Some types of lasers make use of forbidden transitions: atoms or molecules are brought into an excited state such that the transition to the ground state is forbidden and thus slowed down. This causes the exited state molecules to collect, forming a population inversion. The excited molecules can then undergo stimulated emission in a resonance cavity, producing the laser effect.

Now my question is if 1,2-dioxetanedione can also be made to undergo stimulated emission if the glow stick chemical reaction takes place in a suitable optical resonance cavity. (It looks to me like it should, but my chemistry knowledge is not enough for this.)

Alternatively, if the 1,2-dioxetanedione cannot undergo stimulated emission, could a suitably chosen dye molecule?

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The activated complex 1,2-dioxetanedione can't undergo simulated emissions as it isn't the emitting molecule even in glow-sticks: it is the source of the activation energy for other dyes.

But most emitting dyes can be used in suitably configured lasers by providing energy as photons (=light) of a higher energy and a suitable wavelength in a suitable device. Whether they would make good lasers depends on a whole bunch of other factors (like how easy it is for them to absorb light, whether the subsequent transitions are forbidden or not (can't easily get population inversion if they are not) and various quantum efficiencies of the relevant conversions in the dye molecule.)

Dye lasers have been known since 1966. They have some advantages over more conventional lasers as they are often wavelength tunable (as dyes tend to have broad emission lines) and can often achieve very short pulses. Rhodamine 6G is a common laser dye but the dyes in a glow-stick may not be as good in lasers, though, in principle, there is no reason why not.

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A nice idea but it is very unlikely indeed that you will be able to make a dye lase either as a amplifier or in a cavity. The energy is transferred from the chemical reaction to the dye very slowly compared to how quickly a typical visible dye molecule fluoresces; usually the fluorescence lifetime is a few nanoseconds. Thus a population inversion will not be built up.

To get dye lasers to work with flash lamps is very hard, more often a Q switched doubled YAG laser is used or for continuous lasing an argon ion laser or cw YAG, in either case a few watts of light power (not electrical power from the wall plug which is greater) is needed. You just could not get this from the chemical reaction in the light stick even if put into a cavity.

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  • $\begingroup$ Would a different choice of "dye" with a longer fluorescence lifetime be possible? And the chemical reaction could be made faster by increasing chemical concentrations and increasing pH, which would also increase the number of dye molecules in an excited state. Also I'm not asking for a very high powered laser. $\endgroup$ – JanKanis Aug 18 '17 at 18:14
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    $\begingroup$ In principle yes, but in practice no; its virtually impossible by orders of magnitude to get a population inversion chemically in a dye: Its hard even with high powered flash lamps or other lasers where the energy is put directly into the dye. (In a few special situations chemical lasers do exist and work in the IR). $\endgroup$ – porphyrin Aug 19 '17 at 9:21
  • $\begingroup$ Does that also take 4-level lasers into account? From the wikipedia description I got the idea that 4 level lasers made it very easy to achieve a population inversion because the lower band was guaranteed to always be (nearly) empty. $\endgroup$ – JanKanis Aug 19 '17 at 12:02
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    $\begingroup$ yes dyes form 4 level lasers; its all relative and 'easy' usually means relative to a 3 level laser. In a dye the lifetime is nanoseconds so that you have to get the energy into the excited state in a comparable time. I don't recall that a dye laser has been made using a chemical reaction only to produce excited states. $\endgroup$ – porphyrin Aug 19 '17 at 15:05

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