Photochemical action plots

[8] The first biological action spectrum was recorded by Engelmann, who used a prism to produce different colors of light and then illuminated cladophora in a bacteria suspension.

Such studies have also been instrumental in identifying DNA as the core genetic material,[11] key wavelengths leading to skin cancer,[12] the transparent optical window of biological tissue,[13] and the influence of color on circadian rhythms.

These studies have been vital in understanding primary contributors to photocurrent generation,[17][18] leading to advancements in materials,[19][20] morphologies,[21][22] and device designs[23][24] for improved solar energy capture and utilization.

These involve a monochromatic light source, often a laser, coupled with a mass spectrometer to record wavelength-dependent ion dissociation in gaseous phases.

[25] These spectra help identify contributing chromophores in molecular systems,[26][27] characterize radical generation and unstable isomers,[28][29] and understand higher state electron dynamics.

The photochemical process' yield or conversion is subsequently measured using sensors like UV-Vis absorption or nuclear magnetic resonance (NMR) frequency changes.

A) Experimental setup featuring an adjustable, monochromatic light source shining from below into a clear vial with the reactive mixture, ensuring consistent photon delivery at each targeted wavelength. B,C) Two examples of action plots of two different photo initiators displaying their absorbance (blue line) and experimentally determined monomer conversion.