Halides of elements

In the ammoniates of the halides of elements beyond the aluminium group, this dipole ion attraction may be replaced by the... 

The thermochemical aspects of these reactions have been discussed in terms of heats of formation of the halides of elements of the iron group, and of the acceptor metal (75). The yield of carbonyls was especially favored with the iodides and also with sulfides or sulfur-containing materials (76). With iron and cobalt iodides the reaction is facilitated by formation of the carbonyl iodide as an intermediate. 

Table A selection of oxides and halides of elements from the 4d and 5d series. M represents either of the two elements from the corresponding group, and X any halogen unless exceptions are specified...

Apparatus for the study of the volatile halides of elements 104 and 105 (reproduced with permission from J.V. Kratz, J. Alloys Compd., 1994, 213-214, 22). 

The immense number of chemical compounds formed by the halogens provides chemists with an extraordinary database from which numerous chemical and physical phenomena can be correlated with respect to various periodic trends. From databases like Inorganic Crystal Structure Data (ICSD, http //www.fiz-karlsruhe.de ) and International Centre for Diffraction Data (ICDD, http //www.icdd.com) with 67 000 and 25 000 entries, respectively, one can easily make out that halides are one of the dominant classes of compounds besides oxides. Even within the subset of inorganic solids, there is tremendous diversity of composition, stracture, and properties and to summarize this would create its own encyclopedia. Therefore, the discussion in this article is limited primarily to binary halides, their structures, and some of their properties, except halides of elements which are nonmetals. Binary actinide hahdes are discnssed elsewhere see Actinides Inorganic Coordination Chemistry). Complex hahdes (sohd phases containing two or more kinds of metal ions), ... 

From 1969 to 1976 researchers at Dubna reported studies of the volatilities of the halides of elements 104 and 105, suggesting that the halides of these elements behaved similarly to those of their fighter group-4 and group-5 homologues. Because only spontaneous fission was detected, the identity of the species being measured could not be positively attributed to element 104 or 105. 

Halides of elements of group 5 can be represented by AsCh and SbCh. First, arsenic ... 

A., Zimmermann, H. P, and Zvara, I. 1992. Gas phase chromatography of halides of element-104 and Element-105. J Radioanal Nucl ChAr 160, 327-339. 

The mechanism of azide SHS systems reactions is quite complex when using halides of elements to be nitrided. The final nitride formation in this case goes through a number of intermediate species such as NajAlFg with their following reducing or decomposition and simultaneous aluminum nitriding. 

Based on those facts, it can be concluded that the use of halides of elements to be nitrided is rather an effective way to obtain powders with higher purity degree and specific surface. 

The Use ofComplexing Halides of Elements to be Nitrided and Alkaline Metals... 

Cationic polymerization of unsaturated compounds proceeds through the stage of carbanion cations, called also carbocations. Typical catalysts for this reaction are strong protic acids such as sulfuric acid, perchloric and trifluoroctane or the Lewis acids, which include halides of elements III, IV and V groups of the periodic table (Friedel-Crafts catalysts), such as boron trifluoride, aluminum trichloride, tin tetrachloride and titanium tetrachloride. The activity of Friedel-Crafts catalysts increases significantly the presence of small quantities of cocatalysts, that is, ihe compounds which most often are the source of protons. 

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