Perspective abstract

Nature Chemistry 1, 443 - 449 (2009)
Published online: 24 August 2009 | doi:10.1038/nchem.327

Subject Categories: General chemistry | Theoretical chemistry

Charge-shift bonding and its manifestations in chemistry

Sason Shaik1, David Danovich1, Wei Wu2 & Philippe C. Hiberty3

Electron-pair bonding is a central chemical paradigm. Here, we show that alongside the two classical covalent and ionic bond families, there exists a class of charge-shift (CS) bonds wherein the electron-pair fluctuation has the dominant role. Charge-shift bonding shows large covalent–ionic resonance interaction energy, and depleted charge densities, and features typical to repulsive interactions, albeit the bond itself may well be strong. This bonding type is rooted in a mechanism whereby the bond achieves equilibrium defined by the virial ratio. The CS bonding territory involves, for example, homopolar bonds of compact electronegative and/or lone-pair-rich elements, heteropolar bonds of these elements among themselves and with other atoms (for example, the metalloids, such as silicon and germanium), hypercoordinated molecules, and bonds whose covalent components are weakened by exchange-repulsion strain (as in [1.1.1]propellane). Here, we discuss experimental manifestations of CS bonding in chemistry, and outline new directions demonstrating the portability of the new concept.

  1. Institute of Chemistry and The Lise Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel.
  2. State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
  3. Laboratoire de Chimie Physique, Groupe de Chimie Théorique, CNRS UMR 8000, Université de Paris-Sud, 91405 Orsay Cédex, France.

Correspondence to: Sason Shaik1 e-mail:

Correspondence to: Wei Wu2 e-mail:

Correspondence to: Philippe C. Hiberty3 e-mail: