Fluorine oxyfluoride

Three other binary compounds of molybdenum and fluorine are known to exist molybdenum trifluoride [20193-58-2] MoF, molybdenum tetrafluoride [23412-45-5] MoF, and molybdenum pentafluoride [13819-84-6] MoF. Also known are the two oxyfluorides, molybdenum dioxydifluoride [13824-57-2] M0O2F2, and molybdenum oxytetrafluoride [14459-59-7] MoOF. The use of these other compounds is limited to research appHcations. 

Phosphoms oxyfluoride is a colorless gas which is susceptible to hydrolysis. It can be formed by the reaction of PF with water, and it can undergo further hydrolysis to form a mixture of fluorophosphoric acids. It reacts with HF to form PF. It can be prepared by fluorination of phosphoms oxytrichloride using HF, AsF, or SbF. It can also be prepared by the reaction of calcium phosphate and ammonium fluoride (40), by the oxidization of PF with NO2CI (41) and NOCl (42) in the presence of ozone (43) by the thermal decomposition of strontium fluorophosphate hydrate (44) by thermal decomposition of CaPO F 2H20 (45) and reaction of SiF and P2O5 (46). 

Fluorides. Tantalum pentafluoride [7783-71-3] TaF, (mp = 96.8° C, bp = 229.5° C) is used in petrochemistry as an isomerization and alkalation catalyst. In addition, the fluoride can be utilized as a fluorination catalyst for the production of fluorinated hydrocarbons. The pentafluoride is produced by the direct fluorination of tantalum metal or by reacting anhydrous hydrogen fluoride with the corresponding pentoxide or oxychloride in the presence of a suitable dehydrating agent (71). The ability of TaF to act as a fluoride ion acceptor in anhydrous HF has been used in the preparation of salts of the AsH, H S, and PH ions (72). The oxyfluorides TaOF [20263-47-2] and Ta02F [13597-27-8] do not find any industrial appHcation. 

Bismuth pentafluoride is an active fluorinating agent. It reacts explosively with water to form ozone, oxygen difluoride, and a voluminous chocolate-brown precipitate, possibly a hydrated bismuth(V) oxyfluoride. A similar brown precipitate is observed when the white soHd compound bismuth oxytrifluoride [66172-91 -6] BiOF, is hydrolyzed. Upon standing, the chocolate-brown precipitate slowly undergoes reduction to yield a white bismuth(Ill) compound. At room temperature BiF reacts vigorously with iodine or sulfur above 50°C it converts paraffin oil to fluorocarbons at 150°C it fluorinates uranium tetrafluoride to uranium pentafluoride and at 180°C it converts Br2 to bromine trifluoride, BrF, and bromine pentafluoride, BrF, and chlorine to chlorine fluoride, GIF. It apparently does not react with dry oxygen. 

IF7 is a stronger fluorinating agent that IF3 and reacts with most elements either in the cold or on wanning. CO enflames in IF7 vapour but NO reacts smoothly and SO2 only when warmed. IF7 vapour hydrolyses without violence to HIO4 and HF with small amounts of water at room temperature the oxyfluoride can be isolated ... 

Oxygen and fluorine ions have very similar ionic radii. This steric similarity ensures relatively easy substitution of the oxygen in the compounds, by fluorine ions. Such substitution opens up huge possibilities for the synthesis of oxyfluoride compounds with desired crystal structure and properties. 

Ammonium complex fluorometalates are generally susceptible to hydrolysis by water formed in the course of the fluorination process (see 25). Such interactions, resulting in the formation of oxyfluoride metalates can be described as follows ... 

Simultaneous fluorination of niobium oxide and oxides of trivalent metals using an ammonium hydrofluoride melt leads only to oxide-type compounds, MinNbC>4 due to low thermal stability of fluoride or oxyfluoride compounds that contain both niobium and trivalent metals. 

One of the most important parameters that defines the structure and stability of inorganic crystals is their stoichiometry - the quantitative relationship between the anions and the cations [134]. Oxygen and fluorine ions, O2 and F, have very similar ionic radii of 1.36 and 1.33 A, respectively. The steric similarity enables isomorphic substitution of oxygen and fluorine ions in the anionic sub-lattice as well as the combination of complex fluoride, oxyfluoride and some oxide compounds in the same system. On the other hand, tantalum or niobium, which are the central atoms in the fluoride and oxyfluoride complexes, have identical ionic radii equal to 0.66 A. Several other cations of transition metals are also sterically similar or even identical to tantalum and niobium, which allows for certain isomorphic substitutions in the cation sublattice. 

The steric similarity of oxygen and fluorine ions enables the formation of coordination-type structures in some tantalum and niobium oxyfluoride compounds. 

The structure of the crystal has a tendency to utilize steric similarity of its component ions and is defined by the number of anions (oxygen and fluorine) per cation in each oxyfluoride octahedron. 

The proposed model of the structure of oxyfluoride melts corresponds with the conductivity results shown in Fig. 69. The specific conductivity of the melt drops abruptly and asymptotically approaches a constant value with the increase in tantalum oxide concentration. This can be regarded as an additional indication of the formation of oxyfluorotantale-associated polyanions, which leads to a decrease in the volume in which light ions, such as potassium and fluorine, can move. The formation of the polyanions can be presented as follows ... 

The second group is the group of oxyfluorides that are derived from ferroelectric oxides by means of fluorine-oxygen substitution. The basic oxides are usually perovskite, tetragonal tungsten bronze, pyrochlore, lithium tantalate etc. [400]. 

Ammonia solutions are significantly more efficient than ammonium acetate as washing reagents. The process of fluorine content reduction is related to subsequent hydrolysis of fluoride and oxyfluoride contaminants by ammonia. 

This monograph compiles the latest research on the chemistry of complex fluorides and oxyfluorides of tantalum and niobium, and covers synthesis and fluorination processes, crystal structure peculiarities and crystal chemical classification, as well as the behavior of complex ions in fluorine solutions and melts. 

As osmium forms a tetroxide, OsFg might possibly exist, especially in view of the existence of the osmium(VIII) oxyfluorides, but MO calculations indicate the Os—F bond would be weaker in the binary fluoride. It is also likely that non-bonding repulsions between eight fluorines would make an octafluoride unstable [23b],... 

Fluorine and phosphorous NMR data are given in Scheme 7.10 for a number of phosphorous oxyfluorides, and a fluorophosponate ester as well. 

Later, American workers2 described the preparation of this type of compound by a method which necessitated the loss of two-thirds of the fluorine concerned in the reaction. They prepared tetramethylphosphorodiamidic fluoride (bisdimethyl-aminofluorophosphine oxide) (II) by the action of phosphorus oxyfluoride on the calculated quantity of dimethylamine. In addition, it should be emphasized that phosphorus oxyfluoride is a gas and is more difficult than the liquid phosphorus oxydichlorofluoride to manipulate. In Report no. 14 on fluoro-phosphonates to the Ministry of Supply3 it was shown that our reaction could also be applied to the preparation of tetramethyl-... 

The oxyfluorides of La(III) and Y(III) also contain (67, 142, 143) octacoordi-nated metal ions (MO4F4), the metal ions being situated between layers of oxygen and fluorine (cf. other oxyhalides). Zachariasen [142) was able to obtain both rhombohedral and tetragonal modifications for La and Y oxyfluorides with the following M—0 and M—F distances. 

Chlorine monofluoride oxide, 18 328-330 force field of, 18 329, 330 infrared spectrum of, 18 328, 329 stretching force constants for, 18 330 synthesis of, 18 328 Chlorine nitrate fluorination of, 18 332 preparation of, 5 54 Chlorine oxides, 46 109-110, 158 fluorination of, 18 348 Chlorine oxyfluorides, 18 319-389, see also specific compounds adduct formation, 18 327, 328 amphoteric nature of, 18 327, 328 bond lengths, 18 326 bond strengths, 18 323-327 geometry of, 18 320-323 ligand distribution, 18 323 reactivity of, 18 327, 328 stretching force constants, 18 324-327 Chlorine pentafluoride oxide, 18 345, 346 Chlorine trifluoride, reaction with difluoramine, 33 157... 

NQR, 22 216 olefin complexes of, 4 85 in organogermanium compounds, 27 141,143 oxyfluoride, properties of, 11 29 pentacarbonyl dimets of sulfur oxydifluoride imide, 19 203-205 pentafluoride, structure, 27 102 peroxides, 6 325-326 phthalocyanine, 7 54 physical properties of, 11 18 polysulfide complexes, 31 100, 102 envelope conformation, 31 115 synthesis, 31 103-104 [Pt[15]aneS5) f, 35 75, 77 reaction with fluorinated peroxides, 16 120 salts, lattice energy and thermochemistry, 22 52-56... 

Direct chemical oxidation (DCO) is an ex situ treatment technology that uses acidified ammonium or sodium peroxydisulfate solutions to oxidize and destroy organic solids, liquids, and sludges. Acidified peroxydisulfate is one of the strongest oxidants available. It is equal in strength to ozone and exceeded only by fluorine and oxyfluorides. The process is designed to operate within the aqueous phase at low temperatures and ambient pressure. 

Edmond Fremy, who had watched Louyet perform some of his experiments (33), tried to decompose anhydrous calcium fluoride electro-lytically, and did obtain calcium at die cathode, while a gas, which must have been fluorine, escaped at the anode (34). However, because of its tendency to add on to other substances and form ternary and quaternary compounds, Fremy failed in all his attempts to collect and identify the gas. When he allowed chlorine to act on a fluoride, he obtained no fluorine, but only a fluochloride when he used oxygen in place of chlorine, he obtained an oxyfluoride. 

The only stable bismuth(V) halide is BiF5, a white crystalline material, the structure241 of which consists of BiF6 octahedra in infinite trans chains in the manner of a-UF5. It reacts explosively with water to form OF2, 03 and a brown solid (Biv oxyfluoride ) and it is a powerful fluorinating agent. 

Fluorine derivs (cont d) sulfur hexafluoride 6 F147 sulfuric oxyfluoride 6 F148 sulfurous oxyfluoride 6 F148 tetrafluorohydrazine 6 FI 48 tetrafluoromethane see Carbon tetrafluoride 2C64... 

Tellurium and Fluorine Tellurium Totrafluoride, Tellurium Hexafluoride, Tellurium Oxyfluorides. 

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