Structure and stability range of a hexanuclear Th(IV)-glycine complex

Dalton Trans. 2012 Nov 7;41(41):12818-23. doi: 10.1039/c2dt31367g. Epub 2012 Sep 14.

Abstract

A hexanuclear Th(IV)-glycine complex was observed by Th L(3)-edge EXAFS measurements in an aqueous solution. Within the stability range of this complex the positively charged hexanuclear species [Th(6)(μ(3)-O)(4)(μ(3)-OH)(4)(H(2)O)(6)(Gly)(6)(HGly)(6)](6+) was preserved in a crystal with the composition [Th(6)(μ(3)-O)(4)(μ(3)-OH)(4)(H(2)O)(6)(Gly)(6)(HGly)(6)]·(NO(3))(3)(ClO(4))(3)(H(2)O)(3). This complex appears as a result of a competing reaction between hydrolysis and ligation by glycine. At a pH value below the stability range of the hexanuclear complex, crystals with the composition [Th(H(2)O)(3)(HGly)(3)]·(ClO(4))(4)H(2)O were obtained from the solution. Three water molecules in the thorium coordination sphere indicate that this complex occurs prior to the onset of Th(IV) hydrolysis.

MeSH terms

  • Crystallization
  • Glycine / chemistry*
  • Molecular Structure
  • Organometallic Compounds / chemistry*
  • Solutions
  • Thorium / chemistry*
  • X-Ray Absorption Spectroscopy
  • X-Ray Diffraction

Substances

  • Organometallic Compounds
  • Solutions
  • Thorium
  • Glycine