D-Orbital energies

The splitting of the d orbital energy levels when ligands are bonded to a central transition atom or ion has already been mentioned (p. 60). Consider the two ions [Co(NH3)g] and [Co(NH3)g] we have just discussed. The splitting of the d orbital energy levels for these two ions is shown in Figure 13.2. 

N occupy an sp lone-pair in the plane of the ring (or the plane of the local PNP triangle) as in Fig. 12.26a. The situation at P is less clear mainly because of uncertainties concerning the d-orbital energies and the radial extent (size) of these orbitals in the bonding situation (as distinct from the free atom). In so far as symmetry is concerned, the sp lone-pair on each N can be involved in coordinate bonding in the jcy plane... 

Color is a spectacular property of coordination complexes. For example, the hexaaqua cations of 3 transition metals display colors ranging from orange through violet (see photo at right). The origin of these colors lies in the d orbital energy differences and can be understood using crystal field theory. 

SPLITTING OF d ORBITAL ENERGIES IN FIELDS OF OTHER SYMMETRY... 

The only other well-investigated type of transition metal halides are d10 species, including linear AgX and MX2 (M = Zn, Cd, Hg) (Fig. 9). d-Orbital energies are ex-... 

Figure 11. Stereochemistry and d-orbital energy diagram of the tetragonal Cu(H20)g2+ ion.

OM 0, the dyz and d2x orbitals are promoted in energy, the resulting hierarchy of d-orbital energies being... 

A very special complication can arise from the breakdown of the single configuration approximation. This is most likely to be a problem in systems where the d-orbital energy ordering alters drastically during a reaction an example may be the butadiene coupling reaction discussed below. 

Most of the stereochemical arrangements found in these complexes are based oil the octahedron or on the tetrahedron, and may be derived from these configurations by a suitable distortion. Both basic systems have cubic symmetry and d-orbital energies are split into a triplet and a doublet. The group-theoretical notation will be used for their description. ... 

---