Zirconium chloride structure

Zirconium, tetrakis(acetylacetonate)-stereochemistry, 1, 32, 94 Zi rconium, tris(phenylenedithio)-structure, 1, 63 Zirconium alkoxides oligomeric structure, 2,346 Zirconium chloride... 

Other Binary Compounds.—Scandium nitride and zirconium and titanium carbide do not conform with the theoretical radii. It is possible that these crystals do not consist essentially of Sc+3, N 3, Ti+4, Zr+4 and C-4 ions, especially since zirconium and titanium nitride, ZrN and TiN, also form crystals with the sodium chloride structure but possibly also the discrepancy can be attributed to deformation of the anions, which have very high mole refraction values. 

The nitrides and carbides of titanium and zirconium and the carbide of hafnium are extremely hard substances, resembling metals both in appearance and in electrical conductivity. Their formulae approach AxBh but some departure from stoichiometry is possible. Each of these refractory substances has the sodium chloride structure, described alternately (p. 190) as cubic close-packed arrays of metal atoms with the small nonmetal atoms in the octahedral holes. Note, however, that the parent metals themselves do not have cubic close-packed structures. Thus, the older view of such nitrides and carbides as lattices of the parent metals that are expanded to accommodate nitrogen or carbon atoms in the holes (interstices) is not admissible. The nature of the bonding in such refractory nitrides and carbides appears to be linked to the nature of bonding in metals in general, an important and interesting topic, but best pursued in more advanced works. 

The refractory carbides NbC and TaC and the nitride NbN, each with the sodium chloride structure, are also similar to the corresponding zirconium and hafnium compounds. Finally, it may be noted that the same group of complexing agents form complexes with Nb(V) and Ta(V) as with Zr(IV) and Hf(IV) (for example, fluoride, hydrogen peroxide, acetylacetone, and 1,2-dihydroxybenzene). 

This is also the evidence of a substantial fraction of ionicity of zirconium bonds with ligands. However, zirconium forms strong directed bonds. With coordination number 8, it uses hybrid p-orbitals of d sp type, that leads to dodecahedral configuration of bonds. Thus, zirconium compounds are prone to hydrolysis and hydrolytic condensation. In particular, in the solutions of zirconium chloride ZrOCl2 SHjO, a tetramer [Zr4(0H) (H20)sl° is the prevailing form, which is able to participate in further polymerisation processes. According to the data [42], the structure of the tetramer corresponds to the following scheme ... 

A dimeric zirconium(IV) trihydride complex has been synthesized by reaction of LiBHEt3 with the tridentate triaryloxide zirconium chloride complex ZrCl(THF)2(t-Bu-L) (H3(t-Bu-L) = 2,6-bis(4-t-butyl-6-methylsalicyl)-4-f-butylphenol) (equation 14). The solid-state structure shows each zirconium center adopts a trigonal prismatic stracture with a Zr-Zr separation of 3.163(1) A. In solution, the three resulting hydrides appear equivalent on the NMR timescale. Analogous reactivity was observed for the titanium conger. However, in the resulting titanium trihydride, the metals are assigned formal Ti(III) oxidation states. ... 

ZrCl has a homoatomic-layer structure sequenced Cl-Zr-Zr-Cl. Each Zr atom has three neighbours in the adjacent sheet at 3.09 A, six more in the same sheet at 3.42 A and three chlorine atoms on the other side at 2.63 A. Weak chlorine-chlorine interactions between sheets at 3.61 A contrast with the strong metal-metal binding within sheets. These structural features account for the graphitic nature and anisotropic electrical conduction of ZrS. Thermodynamic parameters have been obtained for the reduction of zirconium chlorides. The reaction of ZrC with a melt containing alkali-metal chlorides and titanium chlorides has been investigated. ... 

Geometric structure and molecular parameter data were used by [97VIS/COR] to determine the heat capacity and entropy of the gaseous zirconium chlorides at... 

K. The predicted structure of the tetrachloride is tetrahedral, that of the trichloride is planar and the dichloride is linear. From the measured and estimated data, [97V1S/COR] calculated the following heat capacity and entropy values for the gaseous zirconium chlorides ... 

Zirconium, tetrakis(acetylacetonate)-stereochemistry, 32 Zirconium, tetrakis(acetylacetone)-stercochemistry, 94 Zirconium, tris(phcnylenedithio)-structure, 63 Zirconium chloride (ZrCl) structure, 27 2.r6Cli2 structure, 27 Zirconium iodide Zr6li2... 

Hwu, S.-J., Ziebarth, R. P., von Winbush, S., Ford, J. E. Corbett, J. D. (1986). Synthesis and Structure of Double-Metal-Layered Scandium, Yttrium, and Zirconium Chloride Carbides and Nitrides, M2CI2C and M2CI2N, Inorg. Chem. 25, 283-287. 

Zhang, J. Corbett, J. D. (1991a). Zirconium Chloride Cluster Phases Centered by Transition Metals Mn-Ni. Examples of the NbgF jg Structure, Inorg. Chem. 30, 431 -435. 

Ziebarth, R. P. Corbett, J. D. (1989a). Centered Zirconium Chloride Clusters. Synthetic and Structural Aspects of a Broad Solid-State Chemistry, Acc. Chem. Res. 22, 256-262. 

Refractory Fibers Recently, zirconia-based insulating material with a low density and a low thermal conductivity has been developed in the form of fibers, paper, felt, board and shaped articles. The material is a cubic zirconia soHd solution stabilized with yttria, and has a maximum usable temperature of >2100 C. The innovative fabrication technique involves the use of an organic precursor fiber as a structural template, impregnated with an aqueous solution of zirconium chloride and yttrium chloride. The metallic salts are deposited within the organic fiber, which can subsequently be burned off by a controlled oxidation. The hollow remainder is then fired at a sufficiently high temperature (800-1300 °C) so as to induce crystallization, after which the oxide particles are sintered to develop a ceramic bond. Other techniques to produce refractory fibers involve phase inver-... 

In order to obtain compounds with Ti-O-P and Zr-O-P units, the hexaethoxy-derivative, NsPaCOEOg, was treated with titanium and zirconium tetrachlorides. In each case, hygroscopic solids of the type NaPaCOEOiOaMCU (M = Ti or Zr) and ethyl chloride were obtained. The degree of polymerization of these solids was 1.6—1.8, and on the basis of their i.r. and n.m.r. spectra, two alternative structures, (46) and (47), were proposed. In an alternative route to the same type of compound, N3P3CI6 was treated with tetra-n-butoxytitanium in o-xylene. Butyl chloride was liberated and a solid was obtained which has been assigned the structure (48). Its thermal decomposition was studied by differential thermal analysis. 

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