Structure and reactivity of a mononuclear gold(II) complex
Related Experiment Video
Updated: Feb 18, 2026

Synthesis and Characterization of Amphiphilic Gold Nanoparticles
Published on: July 2, 2019
Sebastian Preiß1, Christoph Förster1, Sven Otto1,2
1Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg-University, Duesbergweg 10-14, D-55128 Mainz, Germany.
Abstract:
Mononuclear gold(II) complexes are very rare labile species. Transient gold(II) species have been suggested in homogeneous catalysis and in medical applications, but their geometric and electronic structures have remained essentially unexplored: even fundamental data, such as the ionic radius of gold(II), are unknown. Now, an unprecedentedly stable neutral gold(II) complex of a porphyrin derivative has been isolated, and its structural and spectroscopic features determined. The gold atom adopts a 2+2 coordination mode in between those of gold(III) (four-coordinate square planar) and gold(I) (two-coordinate linear), owing to a second-order Jahn-Teller distortion enabled by the relativistically lowered 6s orbital of gold. The reactivity of this gold(II) complex towards dioxygen, nitrosobenzene and acids is discussed. This study provides insight on the ionic radius of gold(II), and allows it to be placed within the homologous series of nd9 Cu/Ag/Au divalent ions and the 5d8/9/10 Pt/Au/Hg 'relativistic' triad in the periodic table.
More Related Videos
07:08In Situ Synthesis of Gold Nanoparticles without Aggregation in the Interlayer Space of Layered Titanate Transparent Films
Published on: January 17, 2017
08:21A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions
Published on: February 5, 2016
Related Concept Videos
Formation of Complex Ions
Complexation Equilibria: Factors Influencing Stability of Complexes
Coordination Number and Geometry
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
Valence Bond Theory