Definition of "photochemistry" [pho•to•chem•is•try]

• The chemistry of the effects of light on chemical systems. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The goal of this “Expose” experiment is to understand the effects of zero gravity and ultraviolet and other cosmic radiation on PAHs, and it focuses especially on photochemistry, the changes that occur when different forms of light hit the compounds."
• "For how the energetic cycles of that power the cell emerged, that alone has only entertained many interesting possibilities, hot core and cooler oceans, reducing ocean/sea floor/land and more oxidizing atmosphere, molecules generated by incubation in space and subsequent infall to earth, reacting with terrestrial molecules, photochemistry (from a uv-rich sun), concentration gradients of a wide variety of sorts, reactions of molecules produced by energetic processes involving meteor impact/burnup."
• "As a National Science Foundation Graduate Research Fellow, her research focused on the composition and photochemistry of secondary organic aerosol, as well as biogenic emissions of atmospherically relevant trace gases."