See also: Electronegativities of the elements (data page) There are no reliable sources for Pm, Eu and Yb other than the range of 1.1–1.2; see Pauling, Linus (1960). The Nature of the Chemical Bond. 3rd ed., Cornell University Press, p. 93.
^The electronegativity of francium was chosen by Pauling as 0.7, close to that of caesium (also assessed 0.7 at that point). The base value of hydrogen was later increased by 0.10 and caesium's electronegativity was later refined to 0.79; however, no refinements have been made for francium as no experiment has been conducted. However, francium is expected and, to a small extent, observed to be more electronegative than caesium. See francium for details.
^See Brown, Geoffrey (2012). The Inaccessible Earth: An integrated view to its structure and composition. Springer Science & Business Media. p. 88. ISBN9789401115162.
Separate values for each source are only given where one or more sources differ.
Electronegativity is not a uniquely defined property and may depend on the definition. The suggested values are all taken from WebElements as a consistent set.
Many of the highly radioactive elements have values that must be predictions or extrapolations, but are unfortunately not marked as such. This is especially problematic for francium, which by relativistic calculations can be shown to be less electronegative than caesium, but for which the only value (0.7) in the literature predates these calculations.
A.L. Allred, J. Inorg. Nucl. Chem., 1961, 17, 215.
J.E. Huheey, E.A. Keiter, and R.L. Keiter in Inorganic Chemistry : Principles of Structure and Reactivity, 4th edition, HarperCollins, New York, USA, 1993.
CRC
As quoted from these sources in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition. CRC Press. Boca Raton, Florida, 2003; Section 9, Molecular Structure and Spectroscopy; Electronegativity
Pauling, L., The Nature of the Chemical Bond, Third Edition, Cornell University Press, Ithaca, New York, 1960.
Allen, L.C., J. Am. Chem. Soc., 111, 9003, 1989.
LNG
As quoted from these sources in: J.A. Dean (ed), Lange's Handbook of Chemistry (15th Edition), McGraw-Hill, 1999; Section 4; Table 4.5, Electronegativities of the Elements.
L. Pauling, The Chemical Bond, Cornell University Press, Ithaca, New York, 1967.
L. C. Allen, J. Am. Chem. Soc.111:9003 (1989).
A. L. Allred J. Inorg. Nucl. Chem.17:215 (1961).
Allen Electronegativities
Three references are required to cover the values quoted in the table.
L. C. Allen, J. Am. Chem. Soc.111:9003 (1989).
J. B. Mann, T. L. Meek and L. C. Allen, J. Am. Chem. Soc.122:2780 (2000).
J. B. Mann, T. L. Meek, E. T. Knight, J. F. Capitani and L. C. Allen, J. Am. Chem. Soc.122:5132 (2000).
