The coordination chemistry at gold nanoparticles

In gold nanoparticles the surface metal atoms play a major role, determining their chemical and physical properties by interacting with donor-acceptor species or ligands in a similar way as the related metal complexes. In addition, coherent oscillations of the metal electrons in resonance with the frequency of the exciting light give rise to localized surface plasmons responsible for an enhancement of the local electric field and SERS effect, allowing a wide range of applications in chemistry, biology and nanotechnology. Multifunctional bridging ligands can be employed for simultaneously binding metal ions and surface atoms. The attractive point of this approach is the possibility of exploiting the charge controlled stabilization by the metal complexes, while imparting new characteristics and properties to the modified nanoparticles. As a matter of fact, a new, exciting field of coordination chemistry can be envisaged, combining metal nanoparticles and metal complexes, in the light of supramolecular and surface plasmon resonance effects.