Octahedral ligand structure

Square planar Ni11 macrocyclic complexes are typically yellow, red, or brown in color and absorb around 400 500 nm, depending on the ligand structure. The octahedral Ni11 complexes absorb at 500A100 nm. 

Non-metallocene catalysts have attracted much attention recently.These catalysts generally contain oxygen and/ or nitrogen (and sometimes sulfur and phosphorous) as ligating atoms, and those heteroatoms are often incorporated into a chelate ligand structure. These catalyst precursors often take an octahedral configuration, providing... 

S) such as water, acetonitrile, or Me2SO (7, 10, 12-14, 16, 65, 66). Interconversion between these two forms depends on the ligand structure and reflects a balance between endothermic solvent coordination and exothermic Ni—N bond lengthening in octahedral species. 

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