Rhenium hexafluoride

Raman spectroscopy of [INFRARED TECHNOLOGY AND RAMAN SPECTROSCOPY - RAMAN SPECTROSCOPY] (Vol 14) -rhenium hexafluoride in mfgof [FLUORINECOMPOUNDS,INORGANIC - RHENIUM] (Vol 11)... 

Fluorination of tungsten and rhenium produces tungsten hexafluoride, WF, and rhenium hexafluoride [10049-17-9J, ReF, respectively. These volatile metal fluorides are used in the chemical vapor deposition industry to produce metal coatings and intricately shaped components (see Thin films,... 

Rhenium hexafluoride [10049-17-9J, ReF, is a pale yeUow soHd at 0°C, but a Hquid at ambient temperature. In the presence of moisture it hydroly2es rapidly forming HF, Re02, and HRe04 (see Rheniumand rhenium compounds). It is not safe to store ReF in a glass trap or glass-lined container. Leaks in the system can initiate hydrolysis and produce HF. The pressure buildup causes the system to burst and an explosion may result. 

Rhenium hexafluoride is readily prepared by the direct interaction of purified elemental fluorine over hydrogen-reduced, 300 mesh (ca 48 pm) rhenium powder at 120°C. The reaction is exothermic and temperature rises rapidly. Failure to control the temperature may result in the formation of rhenium heptafluoride. The latter could be reduced to rhenium hexafluoride by heating with rhenium metal at 400°C. 

Rhenium hexafluoride is used for the deposition of rhenium metal films for electronic, semiconductor, laser parts (6—8), and in chemical vapor deposition (CVD) processes which involve the reduction of ReF by hydrogen at elevated (550—750°C) temperatures and reduced (<101.3 kPa (1 atm)) pressures (9,10). 

Rhenium hexafluoride is a cosdy (ca 3000/kg) material and is often used as a small percentage composite with tungsten or molybdenum. The addition of rhenium to tungsten metal improves the ductility and high temperature properties of metal films or parts (11). Tungsten—rhenium alloys produced by CVD processes exhibit higher superconducting transition temperatures than those alloys produced by arc-melt processes (12). 

Dining the reduction of iridium hexafluoride, osmium hexafluoride or rhenium hexafluoride with silicon to the pentafluorides, the hexafluorides must not be condensed directly onto undiluted silicon powder, or explosions may result [1]. The same is true for molybdenum hexafluoride and uranium hexafluoride [2],... 

Palladium(II) oxide, 4825 Palladium(IV) oxide, 4835 Perchloric acid, 3998 Periodic acid, 4425 Permanganic acid, 4434 Peroxodisulfuric acid, 4482 Peroxodisulfuryl difluoride, 4328 Peroxomonosulfuric acid, 4481 Peroxytrifluoroacetic acid, 0666 Platinum hexafluoride, 4371 Platinum(IV) oxide, 4836 Plutonium hexafluoride, 4372 Potassium bromate, 0255 Potassium chlorate, 4017 Potassium dichromate, 4248 Potassium iodate, 4619 Potassium nitrate, 4650 Potassium nitrite, 4649 Potassium perchlorate, 4018 Potassium periodate, 4620 Potassium permanganate, 4647 Rhenium hexafluoride, 4373 Rubidium fluoroxysulfate, 4309 Ruthenium(VIII) oxide, 4862 Selenium dioxide, 4838 Selenium dioxide, 4838 Silver permanganate, 0021 Sodium chlorate, 4039 Sodium chlorite, 4038 Sodium dichromate, 4250 Sodium iodate, 4624 Sodium nitrate, 4721 Sodium nitrite, 4720... 

See Trimethylsilyl azide Rhenium hexafluoride See Other METAL HALIDES, OXIDANTS... 

Raney cobalt alloy, see Aluminium—cobalt alloy, 0049 Raney nickel alloys, see Aluminium—nickel alloys, 0055 Resorcinol diacetate, see 1,3-Diacetoxybenzene, 3285 Resorcinol, see 1,3-Benzenediol, 2325 Rhenium hexafluoride, 4367 Rhenium hexamethoxide, 2599 Rhenium nitride tetrafluoride, 4338 Rhenium, 4884... 

Palladium(II) oxide, 4819 Palladium(IV) oxide, 4829 Perchloric acid, 3992 Periodic acid, 4419 Permanganic acid, 4428 Peroxodisulfuric acid, 4476 Peroxodisulfuryl difluoride, 4322 Peroxomonosulfuric acid, 4475 Peroxytrifluoroacetic acid, 0662 Platinum hexafluoride, 4365 Platinum(IV) oxide, 4830 Plutonium hexafluoride, 4366 Potassium bromate, 0255 Potassium chlorate, 4011 Potassium dichromate, 4242 Potassium iodate, 4614 Potassium nitrate, 4645 Potassium nitrite, 4644 Potassium perchlorate, 4012 Potassium periodate, 4615 Potassium permanganate, 4642 Rhenium hexafluoride, 4367 Rubidium fluoroxysulfate, 4303 Ruthenium(VIII) oxide, 4856 Selenium dioxide, 4832 Selenium dioxide, 4832 Silver permanganate, 0021... 

Only two transition metal heptafluorides are known. Rhenium hep-tafluoride is stable, but osmium heptafluoride is so unstable that no structural results for the solid compound have been reported (4). The rhenium compound is cubic (92) at room temperature, with unit-cell dimension a = 6.26(2) A, which is the same as that for rhenium hexafluoride (Table V). This cubic form is stable to -90°C, when a transition occurs to a form of lower symmetry, for which unit-cell dimensions are unknown (92). 

Rhenium hexafluoride has been described by Ruff and Kwansik 37, The N.B.S.329 give the heat of formation, referring to this work. The paper referred to does not, however, mention the heat of formation of ReFg. Long3i7 uses the N.B.S. value, together with their value of the heat of atomization of rhenium, to give (Re F) ==96 kcal, corrected to our value of the heat of atomization of fluorine. The reliability of this value is unknown to the present author. 

OcUfluorona rfithaleiie Hexafluororbeiuite(V). O tafluoronaphthalene (0.42 mmol) was dissolved in dry trichlorofluoromethane (0.5 mL) at 273 K in a fused silica vessel. A slight excess of rhenium hexafluoride was admitted to the reaction vessel, causing the deep green octafluoro-naphthalene hexafluororhenate(V) to precipitate at the vapor-liquid in-... 

Rhenium hexafluoride was prepared by heating rhenium metal (Johnson, Mathey Mallory) to 250 in gaseous fluorine in a Monel metal bomb. Re being in slight molar excess of that required by the ReFg formula. If ReF.y was present it was... 

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