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dual ionocovalency defined and correlated with Bohr energy levels and spectroscopy:
I ( Iz )C(n*rc-1) = n*(Iz/R)½rc-1
calculating absolute potential energy of all the electronic structure State from 1s to nf and thus can explain almost all chemical observations.
1) Defined confusably: the attraction for an electron is clearly not expected to be the same for different valencies of an element 
2) Correlated limitedly: based on the empirical relation between the electronagtivities of two atoms (H,Cl) and the dissociation energy of the bond formed between them:
Xcl – Xh = (ΔHCL/96.5) ½
extended unconditionally to calculating the electronegativities of all elements.
a) Ignored the Bohr atomic energy levels and spatial ionicity: I (n*, Iz ),thus ignoring the atom Valence state change [3-8]
b) Ignored spatial covalency: C(n*rc-1), thus ignored the orbital overlap, such as COOP [1，9].
1. Zhang, Y. Ionocovalency and Applications 1. Ionocovalency Model and Orbital Hybrid Scales. Int. J. Mol. Sci. 2010, 11, 4381-4406
2. Pauling, L. The Nature of the Chemical Bond IV. The energy of single bonds and the relative electronegativity atoms. J. Am. Chem. Soc. 1932, 54, 3570–3582.
3. Mackay, K.M.; Mackay, R.A.; Henderson, W. Introduction to Modern Inorganic Chemistry, 6th ed.; Nelson Thornes: Cheltenham, UK, 2002; pp. 53–55.
4. Bergmann D. and Hinze, J. Angew, Chem. Int. Ed. Engl. 1996, 35, 150-163.
5. Cherkasov, A.R.; Galkin, V.I.; Zueva, E.M.; Cherkasov, R.A. The concept of electronegativity and the current state of the problem. Russ. Chem. Rev. 1998, 5, 375–392.
6. Portier, J.; Campet, G.; Etoumeau, J.; Shastry, M.C.R.; Tanguy, B. A simple approach to materials design: Role played by an ionic-covalent parameter based on polarizing power and electronegativity. J. Alloys Compd. 1994, 209, 59–64.
7. Murphy，L. R.; Week, T. L.; Allred, A. L.; Allen*,L. C. Evaluation and Test of Pauling's Electronegativity Scale J. Phys. Chem. A, 2000, 104 (24), pp 5867–5871
8. Lenglet, M. Iono-covalent character of the metal-oxygen bonds in oxides: A comparison of experimental and theoretical data. Act. Passive Electron. Compon. 2004, 27, 1–60.
9. Villesuzanne, A.; Elissalde, C.; Pouchard, M.; Ravez, J. New considerations on the
role of covalency inferroelectric niobates and tantalates. Eur. Phys. J. B 1998, 6, 307.