Ferrocene energy-level diagram

The problem is now reduced to one of evaluating the matrix elements. We shall not discuss the details of this process the reading list, Appendix IX, cites several such calculations. Figure 8.20 shows the energy level diagram for ferrocene produced by one of them. 

Figure 8.20 An energy level diagram for ferrocene. The MO energies are those calculated by Shustorovich and Dyatkina, using a self-consistent field procedure. The positions of the ring and iron orbitals on this diagram are only approximate.

Other Bis-cyclopentadienyl Compounds.—It is interesting to give similar accounts of other neutral molecules like ferrocene, where the central iron atom is replaced by Co, Ni, Cr or other atoms of the transition elements. The energy level diagram will not be veiy different from Fig. 11 in all these cases, and we may treat the molecules by adding, or subtracting the requisite number of electrons. 

Theoretical studies by E. Ruch (173-177) proved the correctness of this concept of the bonding, with which the retention of the aromatic character of the ring is in harmony. The nature of the bonding in the dicyclopentadienyl metal compounds was discussed by him in terms of molecular and equivalent orbitals, and on the basis of calculated overlap integrals for ferrocene an energy-level diagram was suggested which... 

The situation is quite different with ferrocene, which has received more theoretical consideration than any other organometallic compound. Available MO energy level diagrams are mainly based on SCF calculations of Dahl and Ballhausen 125>, Shustorovich and Dyatkina 423,424,425 and of Yamazaki 527>. A comparison of these data with those from a Wolfs-berg-Helmholz calculation is given in 179>. For detailed discussion the... 

Fig. 10.1 Schematic molecular orbital energy level diagram for ferrocene. A more accurate diagram is given in Rg. 10.9. (Adapted and reproduced with permission from Shriver, Atkins and Langford, Inorganic Chemistry).

The approximate energy level diagrams of ferrocene and dibenzene chromium are given in Figs. 3-11 and 3-12. 

Sketch the expected CF splitting diagram for the d-orbitals in ferrocene, Cp Fe, whose structure is shown here. Label the d-orbitals, label each energy level with its group theoretical symbol, fill in the electrons, and predict the magnetism. 

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