Gold planar complexes

Like palladium(II) and platinum(II), gold(III) has the d8 electronic configuration and is, therefore, expected to form square planar complexes. The d-orbital sequence for complexes like AuC14 is dx2 yi dxy > dvz, dxz > dzi in practice in a complex, most of these will have some ligand character. 

Most of the (phosphine)gold(III) complexes known in the literature have a square-planar stereochemistry. They are generally stable and can be prepared by two methods oxidation of the corresponding gold(I) complexes, or substitution processes of weakly coordinated ligands. 

Finally, secondary Au- -C bonds have been found in some adducts of the triangular gold(I) complex [Au3(MeN=COMe)3], where they function as electron donors, with nitro-9-fluorenones as acceptors. The solid-state structures of [Au3(MeN=COMe)3]-[2,4,7-trinitro-9-fluorenone] and [Au3(MeN=COMe)3]-[2,4,5,7-tetranitro-9-fluorenone] [50] consist of one-dimensional arrays in which the planar gold(I) trimers and the nearly planar organic molecules are interleaved with the gold trimers, making face-to-face contact with the nitro-aromatic portion of... 

The electron configuration of Au3+ is [Xe]4/145d8, and all known gold(III) complexes are diamagnetic with the low-spin configuration. The vast majority of complexes are square planar,... 

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