Rhombic-pyramidal five-coordinate

Intermediate spin occurs mainly for square- and rhombic-pyramidal five-coordinate iron complexes and also for planar four-coordinate and for asymmetric six-coordinate... 

Five-coordination is as abundant in copper(II) complexes as the six-coordinate elongated rhombic octahedral stereochemistry (Figure 19.1). The regular square-based pyramidal geometry with five equivalent ligands is only of limited occurrence, but does arise in... 

The chlorides of the product can be substituted by other ligands and mono(-dithiolene) complexes [MoO(AdS)2(S2C2Me2)], [MoO(SR)2(bdt)l (R = Ad or 2,4,6-/-Pr3CeH2) and [MoOCl(SC6H2-2,4,6- -Pr3)(bdt)] have been synthesized and characterized (90). These complexes represent the first examples of five-coordinate monodithiolene MovO complexes each has a square-pyramidal structure with an apical oxogroup. Representatives of these MovO centers exhibit rhombic EPR spectra that show some similarities to signals exhibited by the low- and high-pH forms of chicken liver sulfite oxidase (91). 

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