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Hypervalent Compounds

  1. G. Sean McGrady1,
  2. Jonathan W. Steed2

Published Online: 15 DEC 2011

DOI: 10.1002/9781119951438.eibc0089

Encyclopedia of Inorganic and Bioinorganic Chemistry

Encyclopedia of Inorganic and Bioinorganic Chemistry

How to Cite

Sean McGrady, G. and Steed, J. W. 2011. Hypervalent Compounds . Encyclopedia of Inorganic and Bioinorganic Chemistry. .

Author Information

  1. 1

    University of New Brunswick, Fredericton, NB, Canada

  2. 2

    University of Durham, Durham, UK

Publication History

  1. Published Online: 15 DEC 2011


The chemistry of compounds formally exhibiting more than eight valence electrons is introduced and surveyed. The review covers the definition and representation of hypervalent bonding and its orbital description, including recent developments in electron localization function calculations. The synthesis and reactivity of hypervalent compounds is examined including their use in organic synthesis, along with the factors contributing to their stability. Techniques for determining the structures of hypervalent species are described, including gas-phase electron diffraction and vibrational and NMR spectroscopic methods. Novel hypervalent intermediates and transition states are also surveyed, including recently appreciated inter-ligand hypervalent interactions. Particular emphasis is placed on the important topic of pentacoordination. The review includes chemistry of the halogens, chalcogens, pnictides, noble gases, tin, silicon, and a variety of transition metals.


  • hypervalency;
  • phosphorus;
  • tin;
  • silicon;
  • sulfur;
  • iodine;
  • halogens;
  • organic synthesis;
  • inter-ligand hypervalent interactions;
  • octet rule;
  • valence bond;
  • hybridization;
  • molecular orbital;
  • pentacoordination;
  • noble gases;
  • stereochemistry;
  • NMR spectroscopy;
  • vibrational spectroscopy;
  • structure and bonding