Iron-III fluoride

Iron(III) fluoride [7783-50-8] most widely known fluoride of iron. It is light greenish (lime green) in color and the crystals have a rhombic... 

Hydrated iron(III) fluoride [15469-38-2] is easily prepared from yeHow Fe202 and hydrofluoric acid. Dehydration of FeF 3H20 produces... 

The green hexagonal crystals sublime above 1000°C. Iron(III) fluoride is slightly soluble ia water, freely soluble ia dilute HF, and nearly iasoluble ia alcohol, ether, and benzene. It is used as a catalyst ia organic reactions. 

Iron(III) fluoride ttihydrate [15469-38-2] FeF3-3H2 0, crystallizes from 40% HF solution ia two possible crystalline forms. At low temperature the a-form, which is isostmctural with a-AlF 3H2O, is favored. High temperatures favor P-FeF 3H2O, the stmcture of which consists of fluoride-bridged octahedra with one water of hydration per unit cell. 

Iron(II) fluoride, 14 538 Iron(III) fluoride, 14 538 Iron(II) fluoride tetrahydrate, 14 538 Iron(III) fluoride trihydrate, 14 538 Iron fluoroborate hexahydrate, 4 157t, 158, 159... 

The values of AH for the thallium (III) halide systems becomes less exothermic as complex formation proceeds. There are no steps with about the same value of AH , in marked contrast to e.g. Hg2+ and Pd2+. The trend of AH is in fact opposite to that found for several t)q)ical hard-hard interactions, e.g. iron (III) fluoride, lanthanum sulphate and yttrium acetate (Table 1). An even more striking feature of the thallium (III) halides is that AS°n is approximately constant for all steps. This is indeed different not only from ions such as In +, Cd2+ and Zn +, where reversals of the decreasing trend of AS°n occur for certain steps, but also from Hg2+ and Pd + where the higher steps have a much lower value of ASn than the earlier ones. 

Corrosion of the cell body occurs when the electrolytic current has stopped. Corrosion products, such as iron(III) fluoride, arc a cause of polarization. The cathodic protection method is applied to prevent this corrosion problem. Iron(III) fluoride can be eliminated from the electrolyte as a precipitate on addition of sodium fluoride. 

Fullerenes C60 and C70 are successfully fluorinated54 with manganese(III) fluoride. In a Knudsen cell at 560-650 JC, the major product from C60 is C60F36, whereas in a sealed tube at 330°C, the oxide C60F36O is the major product, with a little C60F34. Fluorination of C70 in a sealed tube at 390°C gives mainly C70F38, with some of the F,6 and F40 compounds. The use of cobalt(III) fluoride and iron(III) fluoride is mentioned, but without details. 

In addition to the traditional catalysts aluminum trifluoride, chromium oxyfiuoride and iron(III) fluoride, published references to chlorofluorocarbon disproportionation reactions describe zinc aluminate (ZnAl,04)l> and nickel(II) chloride on "/-aluminum oxide as carriers.20... 

Six grams (0.053 mole) of iron(III) fluoride is mixed thoroughly with 60 g. (0.1 mole) of purified-grade sodium meta-phosphatet in a beaker and the contents are transferred to the carbon crucible. The crucible is placed in the reaction chamber and is heated to 925°C. at the rate of 75°C./hour in a flowing argon atmosphere. The crucible is allowed to equilibrate at 925°C. for 1 hour. The center electrode is inserted to a depth of in. and a current of 250 mA. (61 mA./cm.2) is used. A constant current source is used to maintain the desired current. The electrolysis should be carried out from 12 to 24 hours to give a sufficient yield. After electrolysis the melt is cooled to room temperature at the rate of 75°C./hour. The crucible is cut to expose the reaction boule, and the excess melt is removed by leaching in hot, dilute hydrochloric acid. Free carbon is removed by flotation with methylene iodide(diiodomethane). The product is in the form of metallic needles and small crystallites with a yield of 0.5-1 g. 

In 1956, it was reported that heating equimolar quantities of phosgene and calcium fluoride at 500 C in a steel bomb gives CF (1%), CCIF3 (65%), CCl Fj (30%), CCI3F (5%), a trace of CCl, and some COFj and COCIF the formation of the fluoromethanes is promoted by the presence of aluminium(ni) fluoride, tin(IV) fluoride, iron(III) fluoride or antimony(V) chloride [1454] ... 

Iron(III) fluoride F3Fe 367 0.58 Manganese(II) sulfide (a form) MnS 1530 26.1... 

Germanium(IV) chloride GeCl4 -72 Iron(III) fluoride trihydrate EeEsBHsO +7870... 

Electrochemical activity of iron-III fluoride (FeFs) was first reported by Arai et al. [125]. The compound has theoretical capacity of approximately 200 mAh/g in the 4.5-2.5 V region and 400 mAh/g in the 2.5-1.5 V region. Li et al. [12] and Amatucci and co-workers [13, 14, 126] have since proposed reaction mechanisms for the higher and lower voltage windows ... 

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