Effect of Impurities, Oxygen, and Temperature

The effect can easily be eliminated by flushing the solution with an inert gas for some minutes, so that the amount of oxygen dissolved drops by approximately three orders of magnitude (this is frequently carried out also with radical reactions). At any 

In fact, this characteristic has even more general implications. Photochemical reactions tend to be (relatively) independent of the conditions (except when the nature of the excited state changes, see above), and thus the primary photoproduct can be created under different conditions (temperature, viscosity, protidty, etc.), a fact that provides such methods with an unparalleled versatility. 

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