Bismuth structure

Keywords Aluminum, Gallium, Antimony, Bismuth, Structures... 

Tetraphenylbismuthonium diphenylbis(trifluoroacetato)bismuthate (equation 51)182 contains a distorted tetrahedral cation and an anion (69), the structure of which has been interpreted in terms of a stereochemically active lone pair. This appears to be the only four-coordinate trigonal bipyramidal bismuth structure established to date in antimony chemistry these types... 

While many different structural types are known for heterocycles containing arsenic, antimony, or bismuth, structural diversity comes from the expanded CN that are available with these heteroatoms. Throughout the Chapter, the letter E, as used in the ring, represents As, Sb, or Bi and its use is explained in the text. Scheme, or Equation. In general, few ring systems exist that contain ring bound heteroatom substituents, and as a result, hydroxy-oxo, amino-imino, and thiol-thioxo tautomerism is nearly nonexistent. 

The actual structure at a vapor-liquid interface can be probed with x-rays. Rice and co-workers [72,73,117] use x-ray reflection to determine the composition perpendicular to the surface and grazing incidence x-ray diffraction to study the transverse structure of an interface. In a study of bismuth gallium mixtures. 

Arsenic dissolves in concentrated nitric acid forming arsenicfV) acid, H3ASO4, but in dilute nitric acid and concentrated sulphuric acid the main product is the arsenic(III) acid, HjAsOj. The more metallic element, antimony, dissolves to form the (III) oxide Sb O, with moderately concentrated nitric acid, but the (V) oxide Sb205 (structure unknown) with the more concentrated acid. Bismuth, however, forms the salt bismulh(lll) nitrate Bi(N03)3. 5H,0. 

Bismuth heterocycles, 1, 539-561 Bismuthiol I metal complexes, 6, 565 IR spectra, 6, 552 ring structure, 6, 561 structure, 6, 557 Bismuthiol II metal complexes, 6, 565 IR spectra, 6, 552 Bisnorisopenicillin, 7, 332, 333 Bisnorpenicillin V, 7, 331 Bis( l,3,4-oxathiazol-2-ones) applications, 6, 945 Bisoxiranes synthesis, 7, 42 Bi(spiroisoxazolines) synthesis, 6, 108 Bi(spirophosphoranes) polytopal rearrangements, 1, 529 reactions, 1, 535 Bispyranones synthesis, 3, 793 a,oj-Bispyranones, alkylene-irradiation, 3, 678... 

The effect of impurities in either structural material or corrosive material is so marked (while at the same time it may be either accelerating or decelerating) that for rehable results the actual materials which it is proposed to use should be tested and not types of these materials. In other words, it is much more desirable to test the actual plant solution and the actual metal or nonmetal than to rely upon a duphcation of either. Since as little as 0.01 percent of certain organic compounds will reduce the rate of solution of steel in sulfuric acid 99.5 percent and 0.05 percent bismuth in lead will increase the rate of corrosion over 1000 percent under certain conditions, it can be seen how difficult it would be to attempt to duplicate here all the significant constituents. 

This approach is an alternative to quantitative metallography and in the hands of a master gives even more accurate results than the rival method. A more recent development (Chen and Spaepen 1991) is the analysis of the isothermal curve when a material which may be properly amorphous or else nanocrystalline (e.g., a bismuth film vapour-deposited at low temperature) is annealed. The form of the isotherm allows one to distinguish nucleation and growth of a crystalline phase, from the growth of a preexisting nanocrystalline structure. 

Bismuth(V) oxide and bismuthates are even less well established though a recent important development has been the synthesis and structural characterization of LisBiOs, prepared by heating an intimate mixture of Li20 and Q -Bi203 at 650° for 24 h in dry O2. The structure is of the defect rock-salt type with an ordering of... 

The radius of the second cation in known MuNbOFs, MU2Nb03F3 and Mul2Nb05F compounds containing bi- and trivalent metals, is usually similar to that of niobium s ionic radius. Such compounds cannot be considered as having an island-type structure and will be discussed later on. Only bismuth-containing compounds (Bi3+) display the presence of different cationic sublattices in their crystal structure. 

Fig. 28 shows the crystal structure of Bi2Nb05F with a space group of I4/mmm - D. Bismuth ions, along with anions, form Bi202 type Bi2(0,F)2... 

Bismuth, tris(dipropyldithiophosphonium)-stereochemistry, 1, 81 Bismuthate, hexabromo-structure, 1,73 Bismuthate, hexachloro-structure, 1, 73 Bismuthate, hexaiodo-structure, 1, 73... 

The pc-Bi/aqueous solution interface has been studied mainly by Palm et a/.666-669 Ea= and other fundamental characteristics were obtained. The electrical double-layer structure at a bismuth solid drop electrode with remelted surface (BiDER/H20) was investigated by Salve... 

The radii in the lowest row of the table were obtained by a number of approximate considerations. For instance, if we assume the bismuth radius to bear the same ratio to the interatomic distance in elementary bismuth as in the case of arsenic and antimony, we obtain (Bi) = 1.16— 1.47 A. A similar conclusion is reached from a study of NiSb and NiBi (with the nickel arsenide structure). Although the structures of the aurous halides have not been determined, it may be pointed out that if they are assumed to be tetrahedral (B3 or Bi) the interatomic distances in the chloride, bromide, and iodide calculated from the observed densities1) are 2.52, 2.66, and 2.75 A, to be compared with 2.19, 2.66, and 2.78 A, respectively, from pur table. 

Asl3 and Bils. Heyworth and Braekken4) in their studies of the hexagonal crystals Asls and Bils assigned to them structures in which each arsenic or bismuth atom is surrounded by six equidistant iodine atoms, the interatomic distances reported being As—I = 2.97 A and Bi—I = 3.09 A. As in the case of eulytite, we believe that the trivalent atoms are displaced towards three and away from three of these six atoms, until the smallest interatomic distances become As — 7 = 2.54 A and Bi — I = 2.84 A5). 

Bismuth is intermediate in the transition from a metallic to a normal covalent structure each atom shows the effect of its normal tricovalence by having three nearest neighbors, at 3.10 A. and it has also three near neighbors at the larger distance 3.47 A. The respective bond... 

These fissioning nuclei (such as 8tP°i2-211> formed by reaction of Bi209 and a deuteron) have a nearly spherical normal-state structure, resembling that of the doubly magic nucleus seP m208, with an outer core of 16 spherons and an inner core of 4 spherons, shown in Fig. 6. The nucleus is excited, with vibrational energy about 25 Mev (for bismuth bombard-... 

In the early 1950s, in a systematic study, Donges (106-108) discovered most of the chalcogenide halides of antimony and bismuth that are known today, and then solved their structures. 

The phase transiton from a paraelectric to a ferroelectric state, most characteristic for the SbSI type compounds, has been extensively studied for SbSI, because of its importance with respect to the physical properties of this compound (e.g., J53, 173-177, 184, 257). The first-order transition is accompanied by a small shift of the atomic parameters and loss of the center of symmetry, and is most probably of a displacement nature. The true structure of Sb4S5Cl2 106), Bi4S5Cl2 194), and SbTel 108,403) is still unknown. In contrast to the sulfides and selenides of bismuth, BiTeBr 108) and BiTel (JOS, 390) exhibit a layer structure similar to that of the Cdl2 structure, if the difference between Te, Br, and I (see Fig. 36) is ignored. 

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