IONIZATION POTENTIALS ELECTRONIC AND MOLECULAR STRUCTURES OF METAL HALIDES FROM EXTENDED HUCKEL THEORY

An extended Hückel (EH) method utilizing single-exponent one-electron Slater orbitals has been applied to the calculation of ionization potentials, electronic structures, and bond angles for many of the halides of groups I, IIa, IIIa, and IVa. The results compare very well with available experimental data and indicate a useful applicability of the EH method to these ionic molecules. In fact, the success of the calculations relates largely to the ionic nature of halides permitting only a minimum of orbital overlap which suggests that even crude atomic orbitals can lead to a reasonable molecular orbital scheme. The method also proves useful in predicting the electronic properties of radical species such as SiF, SiF3, AlF2, etc. Many of the species dealt with are outside of the present molecular size range of Hartree-Fock methods.