page_title: Photochemistry
hierarchical_section_title: Photochemistry
caption_attribution_description: English: Philips HPK125 UV lamp in a photochemical immersion well reactor 50 mL
context_page_description: Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet, visible light or infrared radiation.
  In nature, photochemistry is of immense importance as it is the basis of photosynthesis, vision, and the formation of vitamin D with sunlight. Photochemical reactions proceed differently than temperature-driven reactions. Photochemical paths access high energy intermediates that cannot be generated thermally, thereby overcoming large activation barriers in a short period of time, and allowing reactions otherwise inaccessible by thermal processes. Photochemistry is also destructive, as illustrated by the photodegradation of plastics.
context_section_description: Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible light (400–750 nm) or infrared radiation (750–2500 nm).
  In nature, photochemistry is of immense importance as it is the basis of photosynthesis, vision, and the formation of vitamin D with sunlight.  Photochemical reactions proceed differently than temperature-driven reactions. Photochemical paths access high energy intermediates that cannot be generated thermally, thereby overcoming large activation barriers in a short period of time, and allowing reactions otherwise inaccessible by thermal processes.  Photochemistry is also destructive, as illustrated by the photodegradation of plastics.
caption: Photochemical immersion well reactor (50 mL) with a mercury-vapor lamp.
exif: {"Image Make": "HTC", "Image Model": "HTC Wildfire", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "128", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "438", "Thumbnail JPEGInterchangeFormatLength": "32000", "EXIF ISOSpeedRatings": "74", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2011:10:06 18:16:33", "EXIF DateTimeDigitized": "2011:10:06 18:16:33", "EXIF ComponentsConfiguration": "YCbCr", "EXIF FocalLength": "353/100", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1952", "EXIF ExifImageLength": "2592", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "314"}