Cobalt, glycinato isomers

Glycine has the structure NH2CH2COOH. It can lose a proton from the carboxyl group and form chelate rings bonded through both the N and one of the O atoms. Draw structures for all possible isomers of tris(glycinato)cobalt(III). 

One of the earliest cases of stereoisomerism among inner complexes, tris(glycinato)cobalt(III), occurs in two forms, violet (a) and red (P). In one of these geometric isomers, all of the amino groups of the glycine molecules are adjacent (fac), while in the other, two of these occupy opposite positions mer). Absorption spectra indicate that the more soluble violet a form is the mer isomer. " ... 

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