![]() As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Its purity is typically measured on a per-mille basis a 94%-pure alloy is described as "0.940 fine". Silver metal is used in many bullion coins, sometimes alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Silver has long been valued as a precious metal. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. Non-Cryst.Silver is a chemical element with the symbol Ag (from Latin argentum 'silver', derived from the Proto-Indo-European h₂erǵ 'shiny, white') and atomic number 47. Bamford, Colour Generation and Control in Glass. in Ion- Beam Modification of Insulators, ed. Mazzoldi, Ion-Beam Modification of Glasses. MacKenzie (Butterworth and Company, London, 1960), p. Simon, in Modern Aspects of the Vitreous State, ed. Primack, The Compacted States of Vitreous Silica (Gordon and Breach, New York, NY, 1975) ![]() Galeener (Pergamn Press, London, 1980), pp. Arnold, Surface and Buk Vibration in Ion Implanted Amorphous Silica, in Physics of MOS Insulators, ed. Zuhr, in Host- Guest Interactions in Ti- implanted Silica, Borosilicate and Aluminosilicate Glasses (Materials Research Society Fall Meeting, Boston, MA, 1993), pp 451–456 Kreibig, Collective Excitations in Large Metal Nanoclusters, in Nuclear Physics in the Study of Atomic Cluster Physics, ed. in Treatise on Materials Science and Technology, vol. Zhang, Optical Effects of Ion Implantation (Cambridge University Press, Cambridge, UK, 1994) Griscom, in Nature of Defects and Defect Generation in Optical Glasses (Photonics West, SPIE, The Photonics Society, 1985), pp 38–47 Kreidl (American Ceramic Society, Westerville, 1991), pp. Friebele, Radiation Effects, in The Optical Properties of Glass, ed. in Materials Science with Ion Beams, vol. White, Structure and Properties of Nanoparticles Formed by Ion Implantation. in Materials Science and Technology, vol. Weeks, Optical and Magnetic Properties of Ion Implanted Glasses. Galeener, in The Physics and Technology of Amorphous SiO 2, ed. Zuhr, in Infrared Reflectance Measurement of Ion- Implanted Silica, Properties and Characteristics of Optical Glasses (San Diego, CA, January 16, 1989, 1988) Marker, A.J., III, Ed. Vollmer, Optical Properties of Metal Nanoclusters (Springer, Berlin, 1995) These differences lead to modifications in the size, shape and spatial distributions of the silver nanoparticles and offer a powerful means of controlling their optical properties. However, differences in chemical reactivity, bond lengths and electronic structure of Sc and Ti produce changes in electronic structure and strain that are sensitively reflected in the reflectance spectra of the Ag nanoparticles. Compaction of the silica due to the ion implantation process appears to be similar for both Sc and Ti implantations, based on the observed shift of the 1,124 cm −1 transverse-optical phonon mode in the infrared reflectance spectrum. In particular, the dichroic response observed for Ag nanoparticles in Sc-implanted silica is, with one exception, in Ti-implanted silica. In this paper, we show that implantation of titanium ions alters the short- and intermediate-range order in the silica and thereby alters the diffusion and nucleation processes that lead to formation of silver nanoparticles. For example, implantation of scandium in fused silica creates a directional optical dichroism due to the different spatial distribution of silver nanoparticles subsequently formed by Ag ion implantation. Metal nanoparticles formed by ion implantation in fused silica exhibit linear and nonlinear optical properties that can be altered by co-doping the silica substrate with transition-metal ions.
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