Breakdown of molecules into smaller units via absorption of light. Flash photolysis, an experimental technique developed by Manfred Eigen, Ronald George Weyford Norrish, and George Porter, studies short-lived chemical intermediates formed in many photochemical reactions. An intense, brief flash of light splits molecules into short-lived fragments, which are analyzed by spectrophotometry in a second, less intense flash.

Learn more about photolysis with a free trial on Britannica.com.