Fenske-Hall scheme

The Fenske-Hall scheme is somewhat different in its development from the above ZDO and extended Hiickel schemes in that it cannot be derived so readily from the ab initio Fock expressions. We proceed to derive the expressions for the Fenske-Hall Fock operator here. 

The Fenske-Hall method is a modification of crystal held theory. This is done by using a population analysis scheme, then replacing orbital interactions with point charge interactions. This has been designed for the description of inorganic metal-ligand systems. There are both parameterized and unparameterized forms of this method. 

Before describing the Fenske-Hall method itself, we will examine an example of the behavior described above. Our example will be ferrocene (Tri -C5H5)2Fe, whose qualitative molecular orbital diagram is shown in Scheme 40.1. The principal bonding... 

The electronic structure of Cp2Ni2( x-S)2(MnCO)3 (S = 1/2 ground state) has been described by Fenske-Hall calculations [19]. Here, we will describe those results first and then compare them with DFT and HFR calculations. The MO diagram shown in Scheme... 

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