Zhang electronegativity is Best up to Bergmann-Hinze’s criterion

Yonghe Zhang ioniccovalent theory applications (33)

Zhang electronegativity is up to Bergmann-Hinze’s criterion.

 

Yonghe Zhang

American Huilin Institute   http://www.amhuilin.com/

 

Bergmann-Hinze in “Angew. Chem. Int. Ed. Engl” proposed a review titled “The electronegativity and Molecular Properties”. In the effort to derive molecular information from atomic properties a criterion of three types of atomic properties were proposed by Bergmann-Hinze.[1]: a) those that can be determined directly by spectroscopy, ionization potentials are strongly suggested, b) those based on theoretical concepts, the quantum mechanics should be correlated, and c) those that can be assigned to the atoms interacting in molecules, covalent radii are preferred. It is a criterion for evaluating all electronegativity and molecular properties.

Obviously, only Zhang electronegativity [2] is up to Bergmann-Hinze’s criterion:

Xz = 0.241 n*( Iz /R) ½rc-2 + 0.775

Where

a) Iz is the ionization potential determined directly by spectroscopy.

b). Based on the quantum mechanics, the term of Schrödinger’s Wave Equation incorporating bond strength is the potential energy Ze2ψ/r.

And according to the Bohr energy model

                        E = - Z2me4/8n2h2 є02 = - RZ2/n2

 we have derived the effective nuclear charge Z* from ionization energy and the effective principal quantum number n*:

Z*=n*( Iz /R)½

c) rc is the covalent radius. It is a distance from nucleus to a charge density wherein the bonding atoms are aligned and localized at very specific bond lengths.



 [1] D. Bergmann and J. Hinze. Angew, Chem. Int. Ed. Engl. 1996, 35, 150-163.

[2] Y. Zhang, J. Molecular Science, (Chinese) 1 (1981) 125.

[3] Y. Zhang, Inorg Chem. 21 (1982) 3886



 



 

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