Chromium , octahedral stereochemistry

From the viewpoint of stereochemistry the most interesting metal complexes are the octahedrally coordinated 1 2 chromium and cobalt complex dyes, which are medially metallized azo and azomethine compounds with functional groups in the o- and o -positions. Three types of isomerism can be discriminated geometrical, N-a, 3, and that arising from azo-hydrazone tautomerism. 

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