Square pyramids five-coordinate compounds

Spot tests, 1, 552 Square antiprisms dodecahedra, cubes and, 1, 84 eight-coordinate compounds, 1,83 repulsion energy coefficients, 1, 33, 34 Square planar complexes, 1,191, 204 structure, 1, 37 Square pyramids five-coordinate compounds, 1,39 repulsion energy coefficients. 1,34 Squares... 

Loss of a ligand to form a square pyramidal, five-coordinate transition state (or possibly an intermediate if the compound is at a local minimum on the energy curve) ... 

Unlike with nitrogen, the five-coordinate compounds Ph5E are known. The P and As compounds have the normal trigonal bipyramidal geometry but Ph5Sb is unexpectedly square pyramidal (2). 

Five coordinate compounds of cobalt are now comparatively common, though only on nitrosyl (dimethyldithiocarbonato) cobalt(I) has a detailed X ray examination been performed (1). This has been shown to have a square pyramidal structure with the N-0 bond inclined at 139 to the pyramidal axis, forming an unsymmetrical tr bond with the cobalt atom. 

Most five-coordinate compounds adopt either the trigonal hipyramidal (TBP) or square pyramidal (SP) structure. Comment on the following structural data. 

Coordination number 5 also has two predominate geometries, square pyramidal and trigonal bipyramidal, that differ only slightly in energy. In fact, such five-coordinate compounds are often examples offluxional compounds, those that exist in... 

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