Optical Isomerism in Complexes
The existence of non-superimposable mirror-image forms of a coordination compound.
Formula / equation
Δ and Λ
Unit
degrees
In depth
Optical activity requires the absence of any plane or centre of symmetry, a condition most easily met by octahedral complexes carrying two or three bidentate chelate rings. The two forms are labelled delta and lambda according to the handedness of the propeller they form.
Examples in the real world
[Co(en)₃]³⁺ existing as a resolvable pair of enantiomers; cis-[Co(en)₂Cl₂]⁺ being chiral while the trans form is not.