Composition crystallization

Mineral CAS Registry Number Approximate composition Crystal Mn%... 

This bismuth-III structure is also observed for antimony from 10 to 28 GPa and for bismuth from 2.8 to 8 GPa. At even higher pressures antimony and bismuth adopt the body-centered cubic packing of spheres which is typical for metals. Bi-III has a peculiar incommensurate composite crystal structure. It can be described by two intergrown partial structures that are not compatible metrically with one another (Fig. 11.11). The partial structure 1 consists of square antiprisms which share faces along c and which are connected by tetrahedral building blocks. The partial structure 2 forms linear chains of atoms that run along c in the midst of the square antiprisms. In addition, to compensate for the... 

An alloy with a specific composition crystallizes its composition may differ from that of the liquid (formation of an intermetallic compound). The composition of the liquid can change during the crystallization process and further intermetallic compounds with other compositions may crystallize. 

Heating of the dimercury(I) compound Hg2As206 gives a mercury(II) compound of the same composition, crystallizing in the PbSb206 structure type with [As206]2 layers and Hg in a pseudo-octahedral environment (r(Hg—O) 235.3 pm).30... 

Analytical method Single element Multiple elements Molecules Surface composition Crystal structure Other... 

Composite crystals, in which the structure can be described as resulting from two or more substructures (related to two or more sets of three dimensional lattices) having different periodicity along at least one direction (chimney-ladder structures, vernier structures, misfit-layer structures, etc.). See the scheme presented in Fig. 3.42. 

A group of crystals show diffraction patterns in which two or more 3D lattices having periods commensurate or incommensurate to each other may be recognized. In other words, the crystal consists of two or more interpenetrating substructures (two or more different atom sets) with different periods at least along one direction (see Fig. 3.42). Names such as composite crystals, vernier structures, misfit-layer structures, and chimney-ladder structures have been used for this group of structures. 

The data in the references provided for each entry in the Appendices are extremely variable. Except for those of the asbestos minerals, the general descriptions of most minerals give little more than cursory mention of their occurrence as fibers. A journal citation indicates some information on composition, crystal structure, size, morphological characteristics, and other... 

Zeolite, zeolite group A collective term for a family of aluminosilicate minerals characterized by framework structures that allow easy access and exchange of cations and small molecules (see chapter 2), The name derives from the Greek terms zein, meaning to boil, and lithos, meaning stone. The term is also applied to synthetic materials of comparable composition, crystal structure, and physical properties (see chapter 2). 

Composition Crystal structure Maximum (nm) Cation neighbours Ref. 

Composition. Crystals deposited from ethanol solution as well-formed thin plates. The fatty acid content of the crystals is given in Table I. For all chain lengths the acid content approximates closely that required for 1 to 1 stoichiometry. This is also the case for most of the acid-soaps prepared by the petroleum ether route the low values of titratable acid in some instances are ascribable to the presence of free soap. 

Phase composition Crystal system Chemical composition Melting point (K) Specific surface (m2/g)... 

In developing these prediction schemes, all aspects of the solid composition, crystal structure, morphology, and history, as well as the electrolyte composition, are reflected in changes in the surface chemistry of the solid and are manifested in the ZPC. The coulombic models used to develop the prediction scheme are grossly oversimplified, and the pro-... 

The structural types described in Chapt. 4 correspond to the crystalline alkoxides. At the same time, M(OR) are much more prone to give amorphous samples due, supposedly, to the nonhomogeneity of their molecular composition. Crystallization occurs only in the cases when the samples contain only one type of aggregate or a regular polymeric structure. 

CHEMICAL COMPOSITION REFINED COMPOSITION CRYSTAL DATA ... 

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