Oxides oxyhalides

It is a relatively long time since the unique character of the stereochemistry of compounds containing bonds between the Si, P, S or Cl atoms and nitrogen or, in the first place, oxygen was recognized on the basis of numerous crystallographic studies on silicates, phosphates, sulfates, chlorates, and phosphazenes, also oxides, oxyhalides, etc. ... 

This article will be concerned with the chemistry of inorganic solid compounds or composites with interesting and useful properties in which the valence of oxygen is —2. Readers interested in molecular oxides, oxyhalides, molecular oxygenyl complexes, peroxides, superoxides, or ozonides should consult established publications and the index of this encyclopedia. 

Group 7 The main volatile compounds formed by the elements of this group are halides, oxides, oxyhalides, and hydroxides. O Table 53.4 shows that many experiments have been carried out, there is a large difference between the adsorption temperatures of the compounds as, for example, ReOs and HRe04. 

Setlur AA, Lyons RJ, Murphy JE, Kumar NP, Kishore MS (2013) Blue Light-Emitting Diode Phosphors Based upon Oxide, Oxyhalide, and Halide Hosts. J Electrochem Soc 2 R3059... 

Oxyhalide Glasses. Many glasses contain both oxide and haUde anions. The introduction of haUdes into an oxide glass typically serves to reduce the glass-transition temperature, T, and to increase the coefficient of thermal expansion. Oxyfluorophosphates have been investigated as laser host... 

Because silver, gold and copper electrodes are easily activated for SERS by roughening by use of reduction-oxidation cycles, SERS has been widely applied in electrochemistry to monitor the adsorption, orientation, and reactions of molecules at those electrodes in-situ. Special cells for SERS spectroelectrochemistry have been manufactured from chemically resistant materials and with a working electrode accessible to the laser radiation. The versatility of such a cell has been demonstrated in electrochemical reactions of corrosive, moisture-sensitive materials such as oxyhalide electrolytes [4.299]. 

Antimony trioxide (SbaOj). It is produced from stibnite (antimony sulphide). Some typical properties are density 5.2-5.67 g/cm- pH of water suspension 2-6.5 particle size 0.2-3 p,m specific surface area 2-13 m-/g. Antimony trioxide has been the oxide universally employed as flame retardant, but recently antimony pentoxide (SbaOs) has also been used. Antimony oxides require the presence of a halogen compound to exert their fire-retardant effect. The flame-retarding action is produced in the vapour phase above the burning surface. The halogen and the antimony oxide in a vapour phase (above 315 C) react to form halides and oxyhalides which act as extinguishing moieties. Combination with zinc borate, zinc stannate and ammonium octamolybdate enhances the flame-retarding properties of antimony trioxide. 

No complexes have at present been authenticated in oxidation states greater than +6, whereas oxyhalide complexes exist where the +8 state is known this parallels trends in the halides and oxyhalides. 

In addition to these types of reactions, liquid HF converts some oxides to oxyhalides. For example, the reaction of permanganate can be shown as follows ... 

As mentioned in the previous section, transition metals in high oxidation states exhibit behavior that is similar to that of some nonmetals. Vanadium(V) does this with the formation of oxyhalides having the formulas VOX3 and V02X. 

Because the highest oxidation state of Cr is + 6, it forms oxyhalides that have the formula Cr02X2 and are known as chromyl halides. However, in the case of the fluorine compound, CrOF4 is also known, as well as some oxyhalides having the formula CrOX3. Some reactions that yield chromyl halides are the following ... 

In Chapter 14, it was shown that oxyhalides of phosphorus can be obtained by the reaction of oxides with halides. One such reaction is... 

Antimony oxide is known as a flame retardant synergist when used in combination with halogen compounds. Volatile antimony oxyhalide (SbOX) and/or antimony trihalide (SbX3) are formed in the condensed phase and transport the halogen into the gas phase (3). It has been suggested that antimony is also a highly active radical trap (4). 

Plutonium nitride, 19 691 Plutonium oxalates, 19 691 Plutonium(IV) oxide, 19 669 Plutonium oxides, 19 688-689 Plutonium oxyhalides, 19 689-690 Plutonium pnictides, 19 691 Plutonium-producing reactors, storage of radioactive waste from, 25 855 Plutonium radioisotopes, 21 319 Plutonium refractory compounds, 19 687 Plutonium reprocessing plants, 19 686 Plutonium silicides, 19 690-691 Plutonium solutions, self-radiolysis of, 19 694... 

Thorium metal, 24 759-761 in alloys, 24 760-761 preparation of, 24 759-760 properties of, 24 760-761 reactions of, 24 761 Thorium nitrate, 24 757, 766 Thorium oxalates, 24 768-769 Thorium oxide, 21 491 Thorium oxides, 24 757, 761-762 Thorium oxyhalides, 24 762 Thorium perchlorate, 24 764 Thorium phosphates, 24 765-766 Thorium pnictides, 24 761 Thorium sulfate, 24 764 Thorium-uranium fuel cycle, 24 758-759 Thorocene, 24 772 Thorotrast, 24 775-776 3A zeolite. See Zeolite 3A Three-boiling beet sugar crystallization scheme, 23 463-465 Three-color photography, 19 233-234 3D models, advantages of, 19 520-521 3D physical design software, 19 519-521 3D QSAR models, 10 333. See also QSAR analysis... 

Chromium(vi) Complexes.—These studies have been virtually confined to oxyhalide and oxide systems. 

Table 5-9 Bond Distances in Transition-Metal Oxides, Halides and Oxyhalides... 

Oxyhalides are another type of volatile inorganic precursors, which have been used in only a few studies, however. For instance, timgsten oxyfluo-ride (WO F ) and H2O have been used as precursors in the deposition of WO3 [48], while Cr02Cl2 together with CH3OH as an oxygen source have been used in the deposition of chromium oxide [49]. 

Compounds of the formulas Re(CH3)6, ReO(CH3)4, Li e CH ] [60975-25-9], Re02(CH3)3 [56090-011-8], and Re03CH3 [70197-13-6] have been prepared. The first two compounds were obtained from reaction of rhenium halides or oxyhalides and methyllithium the last three were formed from the species by oxidation or reduction reactions. The use of these hydride and alkyl complexes as catalysts is under investigation. 

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