Editing Coordination complex (section)

=====Optical isomerism=====
[[Optical isomerism]] occurs when a complex is not superimposable with its mirror image.  It is so called because the two isomers are each [[optically active]], that is, they rotate the plane of [[polarized light]] in opposite directions. In the first molecule shown, the symbol Λ (''[[lambda]]'') is used as a prefix to describe the left-handed propeller twist formed by three bidentate ligands.  The second molecule is the mirror image of the first, with the symbol Δ (''[[delta (letter)|delta]]'') as a prefix for the right-handed propeller twist. The third and fourth molecules are a similar pair of Λ and Δ isomers, in this case with two bidentate ligands and two identical monodentate ligands.<ref>{{Cite book|isbn=978-0-13-841891-5 |last=Miessler|first=Gary L.|author2=Donald Arthur Tarr|title=Inorganic Chemistry|year=1999|pages=315, 316|chapter=9|publisher=Prentice Hall }}</ref>

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Image:Delta-tris(oxalato)ferrate(III)-3D-balls.png|[[Potassium ferrioxalate|{{chem2|Λ\-[Fe(ox)3](3-)}}]]
Image:Lambda-tris(oxalato)ferrate(III)-3D-balls.png|{{chem2|Δ\-[Fe(ox)3](3-)}}
Image:Delta-cis-dichlorobis(ethylenediamine)cobalt(III).png|[[cis-Dichlorobis(ethylenediamine)cobalt(III) chloride|{{chem2|Λ\-''cis''\-[CoCl2(en)2]+}}]]
Image:Lambda-cis-dichlorobis(ethylenediamine)cobalt(III).png|{{chem2|Δ\-''cis''\-[CoCl2(en)2]+}}
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