Metal array

The idealized structure of the [ Ag6(SPh)8]2 cage is (6e) with the four central Ag atoms trigonally coordinated, and the two outer Ag atoms almost linearly coordinated.29 The edge-bridged tetrahedron of metal atoms occurs in [Au6(Ph2PCH2CH2CH2PPh2)4]2+ but the loosely connected metal array is distorted due to the absence of Au—Au bonding.220... 

Nine-metal arrays in conventional coordination clusters are the confacial bioctahedron and two M4 cubanes linked through a non-cluster metal atom among naked metal clusters the M9 polyhedron is the tricapped trigonal prism or the monocapped square antiprism, and in gold clusters the metal array is the centred cube, the centred crown, or a fragment of the centred icosahedron. 

This reduction in symmetry of the metal array occurs in Pdi0( i3-CO)4(p-CO)g(PBu3)6,304 where there is also a lower symmetry set of ligand connections. There is still a (Pd )6 octahedron, capped by (p3-CO) on four tetrahedrally arrayed faces, but the Pd° are located unsymmetrically over the remaining faces, being connected by doubly-bridging carbonyls to the equatorial Pd only. The Pd° thereby constitute a disphenoid rather than a tetrahedron. Phosphine ligands terminate the Pd° and the two axial Pd . 

Although the distinction is not always clear, ternary nitrides (and nitrides in general) often are classified into two groups (1) intermetallic-type and (2) ionic/covalent-type. Intermetallic nitrides are those in which metal-metal (M-M) interactions are dominant and where the nitrogen atoms are interstitial within the metal array.3 Because these phases are stabilized by M-M interactions, the structure and physical properties are similar to those of many other metallic systems, such as alloys, metals, and... 

Closely related are [Bi4Co9(CO)16]2 and [Bi8Co14(CO)2o]2-, the metal cores of which are given as 62A/62B and 63. They may be viewed as tetracapped, tetragonally distorted M8 arrays that also possess interstitial metal atoms. Compound 63 consists of two of the 62 metal frameworks fused about one of the Co4 faces. Compared to 59, 62 is seen to be missing two of the ju4-E groups. In addition, the Co-Co bonds parallel to the C4 axis of the molecule have been broken and have been replaced with four Bi-Coimerstitial interactions. The result is that 61 can be viewed as a cuboc-tahedron, which is more apparent if the compound is viewed from a different perspective (62B). This also emphasizes the close-packed nature of the metal array. 

These novel hexanuclear species display an unprecedented planar rhomboidal metal array consisting of two intact Re2 units and two Cu+ cations. These clusters can be considered as raft-like aggregates and therefore represent a geometric analogue of a metal surface.307... 

The terminal acetylene derivatives Osg(CO)i6(RCCH) (R = Me, Et, Ph) have been shown to react with CO to give Osg(CO)i7(RCCH), (89), in which the acetylene ligand is still intact and sits on the base of the capped pyramidal osmium polyhedron. This compound was found to convert by the action of heat to an isomer in which the proton from the acetylene has been transferred to the metal array. The process is accompanied by an opening up of the metal cluster (Scheme 34). 

Kim JH, Moyer PJ (2007) Laser-induced fluorescence within subwavelength metallic arrays of nanoholes indicating minimal dependence on hole periodicity. Appl Phys Lett 90 131111... 

In practice, specific cluster metal framework geometries are associated with particular electron counts and the number of formal metal-metal bonds present. It is often simplest to analyze structures in terms of these electron counts. Some of the possible metal framework geometries associated with the more common electron counts are illustrated in Fig. 17, and these metal arrays, along with the mode of coordination of the alkyne-substituted ligands, will be used in Section IV,C to order the discussion of the structural types. 

K. Tanaka, A. Tengeiji, T. Kato, N. Toyama, M. Shionoya, A Discrete Self-Assembled Metal Array in Artificial DNA , Science, 299, 1212 (2003)... 

Fan, W., Zhang, S., Minhas, B., Malloy, K. J., Brueck, S. R. J. (2005). Enhanced infiared transmission through subwavelength coaxial metallic arrays. Phys. Rev. Lett. 94 033902. 

Fig. 1.2 (a) The (partial) dispersion relation of SPPs on ID metallic array with period P (solid lines). Part of the dispersion relation now is within the light line (dash line) and excitation of ingoing and outgoing SPPs is possible if the laser and Raman emission at cOexc and cors follow the dispersion relation at iexc and rs (dot lines), (b) Strong Raman intensity is observed from the array when the laser and the Raman emission are impinged at and collected from the array at Oexc and 0RS given as k = sinO n ... 

ID and 2D periodic metallic arrays are fabricated by using IL and thin film deposition. Basically, IL crosses two identical laser beams to spatially create an... 

At the sample stage, a flat mirror is mounted perpendicular to the sample on a rotation stage. As part of the laser beam is reflected by the mirror, it interferes with the nonreflected part to form an interference pattern on the photoresist. The period P is given as P = where 6 is the incident angle [44]. After lithography and baking, the templates are then transferred into an electron-beam or a thermal evaporation thin film deposition system for metallization. As the thickness of the metal film is larger than the skin depth of metal, the metallic arrays are considered as semi-infinitely thick. 

Li J, Xu JB, Ong HC (2009) Hole size dependence of forward emission from organic dyes coated with two-dimensional metallic arrays. Appl Phys Lett 94 241114... 

Chan CY, Xu JB, Waye MY, Ong HC (2010) Angle resolved surface enhanced Raman scattering (SERS) on two-dimensional metallic arrays with different hole sizes. Appl Phys Lett 96 033104... 

C. Multinuclear Linear Metal Arrays with Other... 

Supramolecular Metal Arrays on Artificial Metallo-DNAs and Peptides... 

Recently, we have demonstrated that biopolymers such as DNA and peptides can be chemically reconstructed, and thereby act as template molecules for homogeneous or heterogeneous metal arrays in a programmable manner. This chapter covers our recent approaches to metal arrays on artificial DNAs and cyclic peptides. 

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