Gold cluster

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Gold clusters in cluster chemistry are gold-derived materials that can either be discrete molecules or larger colloidal particles. Both types are described as nanoparticles, with diameters of less than one micrometer.

Discrete gold clusters

Well-defined, molecular clusters are known, invariably containing organic ligands on their exteriors. Two examples are [Au6CP(C6H5)3)6]2+ and [Au9(P(C6H5)3)8]3+.[1]

Colloidal clusters

Gold clusters can be obtained in colloid form. Such colloids often occur with a surface coating of alkanethiols or proteins. Such clusters can be used in immunohistochemical staining.[2] Gold metal nanoparticles (NPs) are characterized by an intense absorption in the visible region, which enhances the utility of these species for the development of completely optical devices. The wavelength of this surface plasmon resonance (SPR) band depends on the size and shape of the nanoparticles as well as their interactions with the surrounding medium. The presence of this band enhances the utility of gold nanoparticle as building blocks for devices for data storage, ultrafast switching, and gas sensors.

Gas-phase clusters

Evidence has been presented for the existence of hollow golden cages with the partial formula Aun- with n = 16 to 18.[3] These cluster compounds with diameter of 550 picometres are observed in the gas-phase after they have been generated by laser vaporization and can be observed in the gas phase by photoelectron spectroscopy. Using similar gas-phase techniques that rely on mass spectrometry, the structures of neutral gold clusters have been investigated and the unique tetrahedral structure of Au20 has been confirmed.[4]

See also

References

  1. ↑ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
  2. ↑ Hainfeld, J. F.; Powell, R. D. New Frontiers in Gold Labeling The Journal of Histochemistry & Cytochemistry, 2000 ,Volume 48, pages 471–480, Online Article
  3. ↑ Evidence of Hollow Golden Cages Bulusu, S.; Li, X.; Wang, L.-S.; Zeng, X. C. Proc. Natl. Acad. Sci. USA 2006, Abstract
  4. ↑ Gruene P, Rayner DM, Redlich B, van der Meer AFG, Lyon JT, Meijer G, Fielicke A (2008). "Structures of Neutral Au7, Au19, and Au20 Clusters in the Gas Phase". Science 321 (5889): 674–6. Bibcode:2008Sci...321..674G. doi:10.1126/science.1161166. PMID 18669858. 

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