Electronegativity the spectroscopic scale

More recently, in 1989, Allen developed his spectroscopic scale, xs, where he equated the electronegativity of an atom to its configuration energy (CE) 

Before leaving this topic, we discuss in more detail the determination of CE and xs values of an element. Table 2.4.3 lists the es and ep, and CE values of the first eight elements in the Periodic Table. For the first four elements, where 

with configuration 2s22p4 and its states 3P, 1D, and 1S, we can determine its multiplet-averaged energy, using the available spectroscopic data. For 

From the electronegativities shown in Figs. 2.4.2 and 2.4.3, it is seen that metals are less electronegative, with xs 2, nonmetals are more electronegative, with xs 2. Around xs 2, we have metalloid elements such as B, Si Ge, Sb, and Bi. Most of these elements have semi-conducting properties. For elements of the same group, xs decreases as we go down the Periodic Table. However, because of relativistic effects, for transition metals from group 7 to 

Variation of electronegativities of representative elements across a given period of the periodic table. Elements of period 6 have electronegativities very similar to those of elements of period 5. For clarity, electronegativities of the elements of period 6 are not shown. 

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