Superconductor inorganic

H, Crystal Engineering of Organic Superconductor/ Inorganic Superconductor Composite Structures... 

Since scanning tunneling microscopy requires flat conducting surfaces, it is not surprising that most of its early application was to study inorganic materials [17, 19, 20, 29-34]. These studies include investigations of catalytic metal surfaces [24, 35-37], silicon and other oxides [21], superconductors [38], gold... 

Allan N L and W C Mackrodt 1997. High-T Superconductors in Computer Modelling. In Catlow C R A (Editor) Inorganic Crystallography, pp. 241-268. 

Ceramic materials are typically noncrystalline inorganic oxides prepared by heat-treatment of a powder and have a network structure. They include many silicate minerals, such as quartz (silicon dioxide, which has the empirical formula SiO,), and high-temperature superconductors (Box 5.2). Ceramic materials have great strength and stability, because covalent bonds must be broken to cause any deformation in the crystal. As a result, ceramic materials under physical stress tend to shatter rather than bend. Section 14.22 contains further information on the properties of ceramic materials. 

A wide class of materials (metals, semiconductors, superconductors, biominerals, water-soluble inorganic and organic compounds, etc.) can be produced using these systems [203-206]. 

The discovery in 1973 that polysulfur nitride (SN)X, a polymer comprised only of non-metallic elements, behaves as a superconductor at 0.26 K sparked widespread interest in sulfur-nitrogen (S-N) chemistry. In the past 30 years, the field of inorganic S-N chemistry has reached maturity and interfaces with other areas of chemistry, e.g., theoretical chemistry, materials chemistry, organic synthesis, polymer chemistry and biochemistry, have been established and are under active development. This interest has been extended to Se-N and, to a lesser extent, Te-N systems. 

The conductors, semiconductors, and superconductors that have been discussed are materials that can be prepared via some type of CVD process. In order to prepare each material, a precursor is required. The precursor chemistry of these materials is based heavily on organometallic and inorganic chemistry. Numerous ligand platforms have been investigated for use in the preparation of suitable CVD precursors. 

Apart from structures that are built of slabs, modular structures that can be constructed of columns in a jigsawlike assembly are well known. In the complex chemistry of the cuprate superconductors and related inorganic oxides, series of structures that are described as tubular, stairlike, and so on have been characterized. Alloy structures that are built of columns of intersecting structures are also well known. Structures built of linked columns, tunnels, and intersecting slabs are also found in minerals. Only one of these more complex structure types will be described, the niobium oxide block structures, chosen as they played a significant role in the history of nonstoichiometry. 

High performance sealants, 22 28 High phosphorus alloys, corrosion performance of, 9 710-711 High pinning Type II superconductors, 23 High pressure apparatus, 13 413 High pressure applications, 13 436-448 in commercial products, 13 436-438 in inorganic chemistry reactions, 13 440—448... 

The results were promising, but did not last long because of the discovery of inorganic ceramics. The ceramics displayed superconductivity without any cooling (Vanderah 1992). Nevertheless, organic metal and superconductors have their advantages, and investigation is carried out in this direction. 

The neutral insulator TMTSF, which shows field-effect conduction with /Th — 0.2 cm s (Nam et al, 2003), when transformed into a Bechgaard salt also becomes superconducting, but at lower temperatures. In this case the perfect segregation of organic and inorganic molecular planes leads to confined electronic systems, which in the normal state are quasi ID. Organic superconductors based on the BEDT-TTF molecule represent the case of pure 2D electronic systems. 

After the initial attempt to prepare alloy and interstitial superconductors, several ceramists, chemists, and materials scientists joined the group of physicists and metallurgists in search of other superconducting materials. These scientists turned to ternary compounds and to more complex systems. From the mid-60 s to the mid-70 s, several new "inorganic materials" were found to exhibit the superconducting phenomenon. 

J.M. Williams and K. Carneiro, "Organic Superconductors Synthesis, Structure, Conductivity, and Magnetic Properties", pp. 249-296, in "Advances in Inorganic Chemistry Radio-chemisiry , Vol 29, Academic Press, Inc. (1985). 

Fortunately, the known superconductors belong to a broad class of inorganic compounds in which the atoms have a layered configuration. Therefore, they can be classified and compared to one another by specifying the composition, the type and the sequence of the layers contained in the unit cell of the structure. This approach is... 

When multicomponent alkoxide solutions, or a single alkoxide and a soluble inorganic salt, are mixed, a multicomponent alkoxide may result. In this way, such complex oxides such as the YBCO superconductor (cf. Section 6.1.2.4) can be formed. Sol-gel processing can also be used to coat fibers for composites and to form ceramics with very fine pore sizes called xerogels. A xerogel commonly contains 50-70% porosity, a pore size of 1-50 nm, and a specific surface area exceeding 100 m /g. 

The range of possibilities for semiconduction is very great, and the applications to the operation of transistors and related devices have revolutionized the electronics industry, but an extensive discussion of these topics is beyond the scope of this text.2 Note, however, that inorganic compounds are receiving intensive attention as the source of semiconductors, superconductors (page 285), and one-dimensional conductors (Chapter 16). 

High-temperature superconductors. 285-288 Hinckley, C, C.t 6l3 Hoffman, R-. 387, 647 Homocyclic inorganic systems, 780-785... 

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