Zhang ionocovalency applications
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Mackay et al , authors of the textbook “Introduction to Modern Inorganic Chemistry” best encompassed the electronegativity that is Zhang Electronegativity when they commented that "A major difficulty of Pauling's electronegativity is that the attraction for an electron is clearly not expected to be the same for different valencies of an element. Zhang  has proposed a set of values, based on covalent radii and ionization potentials, which are defined for each of the main oxidation states (see section 2.17) of the element. These values are one of the more general sets available."
 Y. Zhang,, Inorg Chem., 1982, 21, 3886.
 K. M. Mackay, R. A. Mackay, W.Henderson "Introduction to Modern Inorganic Chemistry", 6th ed., Nelson Thornes, United Kingdom,2002, pp 53-54).