Structural Chemistry

, Volume 30, Issue 5, pp 1629–1630 | Cite as

Paradigms and paradoxes: revisiting the relation of oxidation state and acidity of polyhydride cations

  • Arthur GreenbergEmail author
  • Joel F. LiebmanEmail author
Original Research


Nearly four decades ago, we published a simple chemical regularity: the proton affinity of MHa is higher than that of MHb when “a” is greater than “b.” Some new thoughts about this pattern of chemical energetics are presented in the current study.


Acidity Chemical regularities Oxidation state Polyhydride cations Proton affinity 



  1. 1.
    Greenberg A, Winkler R, Smith BL, Liebman JF (1982) The negatively charged nitrogen in ammonium ion and derived concepts of acidity, basicity, proton affinity, and ion energetics. J Chem Educ 59:367–370CrossRefGoogle Scholar
  2. 2.
    Crabtree KN, Talipov MR, Martinez Jr O, O'Connor GD, Khursan SL, McCarthy MC (2013) Detection and structure of HOON. Microwave spectroscopy reveals an O-O bond exceeding 1.9 Å. Science 342(6164):1354–1357 Acknowledging JFL’s “parental” pride, like Barbara L Smith, Oscar Martinez had also been his undergraduate student. In Martinez’ case, besides classroom experience, he additionally did research with JFL on altogether different species than HOON and related small moleculesCrossRefGoogle Scholar
  3. 3.
    DeKock RL, Barbachyn MR (1979) Proton affinity, ionization energy, and the nature of frontier orbital electron density. J Am Chem Soc 101:6516–6519CrossRefGoogle Scholar
  4. 4.
    Allen LC (1989) Electronegativity is the average one-electron energy of the valence-shell electrons in ground-state free atoms. J Am Chem Soc 111:9003–9014CrossRefGoogle Scholar
  5. 5.
    Rahm M, Zeng T, Hoffmann R (2019) Electronegativity seen as the ground-state average valence electron binding energy. J Am Chem Soc 141:342–351CrossRefGoogle Scholar
  6. 6.
    Aue DH, Webb HM, Bowers MT (1975) Proton affinities, ionization potentials, and hydrogen affinities of nitrogen and oxygen bases. Hybridization effects. J Am Chem Soc 97:4137–4139CrossRefGoogle Scholar
  7. 7.
    Bent HA (1960) Distribution of atomic s character in molecules and its chemical implication. J Chem Educ 37:616–624CrossRefGoogle Scholar
  8. 8.
    Bent HA (1961) An appraisal of valence-bond structures and hybridization in compounds of the first-row elements. Chem Rev 61:275–311CrossRefGoogle Scholar
  9. 9.
    Pomerantz M, Liebman JF (1975) Is 100% s-character necessary? Tetrahedron Lett:2385–2388Google Scholar
  10. 10.
    Garcia GA, Gans B, Tang X, Ward M, Batut S, Nahon L, Fittschen C, Loison J-C (2015) Threshold photoelectron spectroscopy of the imidogen radical. J Electron Spectrosc Relat Phenom 203:25–30CrossRefGoogle Scholar
  11. 11.
    Moore CE (1970) “Ionization potentials and ionization limits derived from the analyses of optical spectra” Nat Stand Ref Data Ser - Nat Bur Stand (U.S.), NSRDS-NBS 34Google Scholar
  12. 12.
    Liebman JF (1972) Why is the oxygen in water negative? J Chem Educ 49:415–417CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of ChemistryUniversity of New HampshireDurhamUSA
  2. 2.Department of Chemistry and BiochemistryUniversity of Maryland, Baltimore County (UMBC)BaltimoreUSA

Personalised recommendations