Factors governing the metal coordination number in metal complexes from cambridge structural database analyses

  • Dudev M
  • Wang J
  • Dudev T
 et al. 
  • 53

    Readers

    Mendeley users who have this article in their library.
  • 65

    Citations

    Citations of this article.

Abstract

The metal coordination number (CN) is a key determinant of the structure and properties of metal complexes. It also plays an important role in metal selectivity in certain metalloproteins. Despite its central role, the preferred CN for several metal cations remains ambiguous, and the factors determining the metal CN are not fully understood. Here, we evaluate how the CN depends on (1) the metal's size, charge, and charge-accepting ability for a given set of ligands, and (2) the ligand's size, charge, charge-donating ability, and denticity for a given metal by analyzing the Cambridge Structural Database (CSD) structures of metal ions in the periodic table. The results show that for a given ligand type, the metal's size seems to affect its CN more than its charge, especially if the ligand is neutral, whereas, for a given metal type, the ligand's charge and charge-donating ability appear to affect the metal CN more than the ligand's size. Interestingly, all 98 metal cations surveyed could adopt more than than one CN, and most of them show an apparent preference toward even rather than odd CNs. Furthermore, as compared to the preferred metal CNs observed in the CSD, those in protein binding sites generally remain the same. This implies that the protein matrix (excluding amino acid residues in the metal's first and second coordination shell) does not impose severe geometrical restrictions on the bound metal cation.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free