Electronegativity thermochemical data

Allred, A.L. Electronegativity Values from Thermochemical Data J. Inorg. Nucl. Chem. 1961, 17, 215-221. 

On the basis of this equation, systematically considering all the available thermochemical data and arbitrarily assigning to the most electronegative element, fluorine, a value of about 4, Pauling was able to prepare a complete electronegativity scale. This is shown in Table 2.1. 

Pauling based his scale on thermochemical data. We shall examine his methods shortly, but we may note that his scale is an arbitrary one chosen so that hydrogen is given a value of about 2 and the most electronegative element, fiuorine, has a value of about 4 ... 

The first known attempt to quantify electronegativity was due to Pauling, who devised an empirical scale, on the basis of thermochemical data. It... 

Having a method to determine relative electronegativities for the elements using molecular thermochemical data required the choice of an origin in order to obtain... 

Allred, A. L. (1961). Electronegativity values from thermochemical data. J. In-org. Nucl. Chem. 17, 215-21. 

Electronegativities, Xp. shown in bold text and rounded to one decimal place, are taken from Allred or from Pauling. The values are based on thermochemical data analysed using Pauling s approach for the elements in their normal oxidation state, viz. for Sc, Y and La, M for Cu. Ag and Au, for the other d-block metals, Ln for the lanthanides and An for the actinides. 

Allred, A. and Rochow, E.G. (1961). Electronegativity Values from Thermochemical Data. Journal of Inorganic Nuclear Chemistry, 17,215-221. 

Electronegativity values have been derived in a number of ways. The first of these was by Pauling and made use of thermochemical data to obtain a scale of relative values for elements. Most electronegativity tables since then have also contained relative values, which do not have units. 

FIGURE 8.7 Electronegativity vaiues based on Pauling s thermochemical data. 

Using thermochemical data for the bonds formation and based on the principle just expressed, Pauling was able to calculate the electronegativity for the main elements from the periodic table (see Table 4.1). 

Bykov GV, Dobrotin RB (1968) Calculation of the electronegativity of fluorine from thermochemical data. Russ Chem Bull 17 226-2271... 

By assigning the value of 2.1 for the electronegativity coefficient of hydrogen (this was done to ensure that all values of the coefficients would be positive), Pauling was able to estimate values for a small number of elements for which the thermochemical data were available. The scale was limited by lack of data and by the perversity of the majority of elements in not forming diatomic molecules. 

Numerical estimates of electronegativity can be based on a variety of properties, not just ionization energy and electron affinity. The first and most widely used electronegativity scale was developed by the American chemist Linus Pauling (1901-1994), who based his scale on thermochemical data. Figure 8.6 T shows... 

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