photochemistry

American  

[foh-toh-kem-uh-stree] / ˌfoʊ toʊˈkɛm ə stri /

noun

1. the branch of chemistry that deals with the chemical action of light.

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photochemistry British  

/ ˌfəʊtəʊˈkɛmɪstrɪ /

noun

1. Also called: actinochemistry.  the branch of chemistry concerned with the chemical effects of light and other electromagnetic radiations

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photochemistry Scientific  

/ fō′tō-kĕm′ĭ-strē /

1. The scientific study of the effects of light and ultraviolet radiation on chemical reactions.

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Other Word Forms

Derived Forms

• photochemic
  adjective
• photochemical
  adjective
• photochemist
  noun
• photochemically
  adverb

Etymology

Origin of photochemistry

First recorded in 1865–70; photo- + chemistry

Example Sentences

"I was just reading about DNA photochemistry – for leisure," she recalls.

From BBC • May 7, 2026

In photochemistry, light energizes the catalyst, and the excited catalyst must encounter another molecule through diffusion in order to pass along an electron.

From Science Daily • Nov. 26, 2025

The complex photochemistry of these tiny particles has outsized, planetary-scale effects.

From Scientific American • Oct. 26, 2023

The meticulous development process of these photos comes down to photochemistry, the marriage between light and science.

From Los Angeles Times • Jan. 6, 2023

Although much information pertaining to photochemistry has been available for years, the absence of powerful light-sources emitting so-called chemical rays in large quantities inhibited the practical development of the science of photochemistry.

From Artificial Light Its Influence upon Civilization by Luckiesh, Matthew