pp 1-28 | Cite as

The Periodic Table as a Career Guide: A Journey to Rare Earths

  • Austin J. Ryan
  • William J. EvansEmail author
Part of the Structure and Bonding book series


This chapter describes a personal journey through the periodic table in which an undergraduate starting research in boron hydride chemistry developed into a professorial researcher in rare earth chemistry. The chapter details how the periodic table became a career guide through connections and developments that led the boron chemist into the rare earth field. Also presented is the evolution of reductive rare earth chemistry which started with just a few +2 lanthanide ions, Eu(II), Yb(II), and Sm(II), and now extends to +2 ions for all the rare earth metals, i.e., Sc and Y, and the lanthanides, La-Lu. The special reactivity of Sm(II), which led to the first lanthanide-based dinitrogen reduction, is described, as well as the rare earth dinitrogen reduction that led to the new Ln(II) ions. Periodic trends in these developments are discussed, and speculation on the future of the rare earth elements in terms of periodic properties is also presented.


Actinide Bismuth Boron Boron hydride Lanthanide Metal vapor reactor Oxidation state Rare earth Samarium Scandium Yttrium 



We thank the National Science Foundation (CHE-1565776) and the Chemical Sciences, Geosciences, and Biosciences Division of the Office of Basic Energy Sciences of the Department of Energy (DE-SC0004739) for support of the rare earth metal and actinide metal parts of this review, respectively.


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Authors and Affiliations

  1. 1.Department of ChemistryUniversity of California, IrvineIrvineUSA

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