Bond orbital model

An empirical relation between band gap and Zunger s orbital electronegativity in s/ -bonded compounds has been determined by Makino (1994a) using a formula derived from the bond orbital model. Based on the bond orbital model and Zunger s orbital electronegativity, new structural maps of AB, AB2 and AB3 compounds between transition metals have been successfully constructed (Makino 1994b). 

E. Honegger, E. Heilbronner, in Theoretical Models of Chemical Bonding, Vol. 3, Z. B. Maksic, Ed., Springer Verlag, Berlin- Heidelberg, 1991, pp. 100-151. The Equivalent Bond Orbital Model and the Interpretation of PE Spectra. 

By fitting the parameters of the Bond Orbital Model to the observed K2 peaks, Harrison and Ciraci (1974) obtained experimental values for the covalent and polar energies. Predicted values will be used here instead, obtained from Eq. (4-17) and the parameters in the Solid State Table. Some discrepancy will be found between these values and the experimental E2 values of Harrison and Circaci. A comparison is made in Fig. 4-5 for the systems for which experimental values of 2 were found. The line drawn there has slope 0.84 this 16 percent... 

We return now to a basis of bond orbitals and antibond orbitals as illustrated in Fig. 3-4. We make the Bond Orbital Approximation in order that we may consider only the four bond orbitals and a four-by-four matrix. We also initially include only matrix elements between nearest-neighbor bonds subsequently, matrix elements between second-neighbor bonds will be added. The resulting bands for the homopolar solids are exactly the same as the bands given by Hall (1952). They were extended to hcteropolar solids by Coulson ct al. (1962) with the use of parameters from Harrison (1973c), they become the bands of the Bond Orbital Model. It is a popular, widely used model. There arc conspicuous discrepancies between this model and accurate bands nevertheless, it can be informative to study the model before adding other matrix elements. 

The summation runs over the first neighbour atoms. Each transfer A, being related to a bond, concerns two atoms and appears in the expression of their charges. This description presents some analogy with the Bond Orbital Model [14]. 

Corcoran, C. T., Weinhold, F. (1980). Antisymmetrization effects in bond-orbital models of internal rotation barriers. Journal of Chemical Physics, 72, 2866 2868. 

Makino Y (1994) Interpretation of band gap, heat of formation and structural mapping for sp-bonded binary compounds on the basis of bond orbital model and orbital electronegativity. Intermetallics 2 55-56... 

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