Tetrahedral complexes energy level diagram

In a nickel-containing enzyme various groups of atoms in the enzyme form a complex with the metal, which was found to be in the +2 oxidation state and to have no unpaired electrons. What is the most probable geometry of the Ni2+ complex (a) octahedral (b) tetrahedral (c) square planar (see Exercise 16.96) Justify your answer by drawing the orbital energy-level diagram of the ion. 

The crystal field energy level diagram for tetrahedral complexes. The d orbitals are split into two sets, with three orbitals destabilized relative to the two others. 

Energy-level diagram for a tetrahedral complex. At the left are the atomic levels the energies of the central atom are labelled with a superscript A. The numbers in parentheses indicate the number of orbitals for each level. There are enough electrons in the complex (thirty-two) to fill sixteen orbitals. 

Figure 6.21 MO energy level diagrams including the effects of 7t bonding in a tetrahedral complex (a) n donor ligands (b) n acceptor ligands...

FIGURE 22.24 Energy-level diagram for a square-planar complex. Because there are more than two energy levels, we cannot define crystal field splitting as we can for octahedral and tetrahedral complexes. 

High-spin Octahedral and Tetrahedral Complexes. For qualitative purposes the partial energy level diagram in Fig. 25-F-3 is useful. In each case... 

Fig. 6.21 A schematic molecular orbital energy level diagram for tetrahedral complexes with only a interactions included. The ligand c electrons are stabilized by interaction with the corresponding metal orbitals. The (three) electrons originally in the metal d orbitals correspond with those distributed between the e(l) and t2(2) molecular orbitals.

Fig. 6.26 A schematic molecular orbital energy level diagram for a tetrahedral transition metal complex in which both a and tc interactions are important.

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