Configuration Energies of the d-Block Elements

Abstract

Configuration energies (CE) of the d-block elements (Groups 3−11) are electronegativities evaluated from the formula CE = (pεs + qεd)/(p + q). εs and εd are the multiplet-averaged one-electron energies of the s- and d-orbitals of atoms which are in the lowest energy of the configurations s n d m and s n -1d m +1, and whose highest known oxidation state is (p + q). The orbital energies are obtained from spectroscopic data. Configuration energies generally increase across a row, with the highest values occurring at nickel, silver, and gold; all are lower than the CE of silicon, the least electronegative nonmetal (except for gold which has a CE equal to that of silicon). Down the groups configuration energies invariably decrease from the first row to the second row; for Groups 7−12, the third-row element has a CE higher than that of the second-row element, due to increasing relativistic stabilization of the 6s orbitals.

Comprehensive definition of oxidation state (IUPAC Recommendations 2016)

“…6 Of several scales discussed in Appendix B of Ref. [1], only the Allen electronegativity (Section 6.1) is truly independent of OS, since it relates to the average valence-electron energy of the free atom [3][4][5], as if the bonds implied in Fig. 1 were abstracted away (Fig.…”

Toward a comprehensive definition of oxidation state (IUPAC Technical Report)

“…A fundamentally different view of EN was presented by L. C. Allen [39,255,256] who argues that EN is an intrinsic free atom property and equates it to the average one-electron energy of the valence-shell electrons of the free atom in its ground state; the configuration energy, CE. For the s-and p-block elements, it is given by CE = (nε s + mε p )/(n + m), where n and m are the number of s-and p-electrons, and ε s and ε p are the experimentally determined, multiplet averaged, one-electron ionization energies [39,255].…”

“…The method has been extended to the d metals, although taking account of their valence electrons is not as straightforward as with the main-group elements [256].…”

“…Although the authors note that Allen's approach carries some ambiguity in enumerating valence d-electrons and it does not take into account the interpenetration of valence-and core orbitals, it is too early to tell how widely these most recent EN values will be accepted and hence Table 4 lists the Allen EN (χ spec values) converted to Pauling units [39,255,256]. Allen's EN values correlate well with the Pauling and Allred-Rochow scales yet avoid their anomalies, perhaps not surprisingly, as χ spec tracks periodic variation in atomic ionization energies.…”

Characteristics of chemical bond and vacancy formation in chalcopyrite‐type CuInSe2 and related compounds

“…Figure 3 shows the schematic molecular orbital diagrams of tetrahedral CuSe 4 7-(a) and InSe 4 4 -(b) clusters. Atomic orbital energies [11,12] of Cu, In and Se are shown in Figs. 3(a) and (b).…”