Editing Photoisomerization (section)

==Coordination chemistry==
Many complexes are often photosensitive and many of these complexes undergo photoisomerization.<ref>{{cite book|
title=Photochemistry and Photophysics of Metal Complexes|author=D. M. Roundhill|publisher=Springer|year=1994|isbn= 978-1-4899-1495-8}}</ref>  One case is the conversion of the colorless cis-[[bis(triphenylphosphine)platinum chloride]] to the yellow trans isomer.
[[File:Cis-trans-PtCl2P2.png|thumb|center|Photoisomerization of PtCl<sub>2</sub>(PPh<sub>3</sub>)<sub>2</sub>]]

Some [[coordination complex]]es undergo change in their spin state upon illumination, i.e. these are photosensitive [[spin crossover]] complexes.<ref>{{cite journal|doi=10.1016/S0010-8545(01)00381-2|title=Photoswitchable coordination compounds|journal=Coordination Chemistry Reviews|volume=219–221|pages=839–879|year=2001|last1=Gã¼Tlich|first1=P.}}</ref>
[[File:Fe(picNH2)3.png|thumb|center|Light-induced spin-crossover of [Fe(pyCH<sub>2</sub>NH<sub>2</sub>)<sub>3</sub>]<sup>2+</sup>, which switches from high and low-spin]]