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Osmium(VI) Fluoride
Osmium hexafluoride, also osmium(VI) fluoride, (OsF6) is a compound of osmium and fluorine, and one of the seventeen known binary hexafluorides. Synthesis Osmium hexafluoride is made by a direct reaction of osmium metal exposed to an excess of elemental fluorine gas at 300 °C. : + 3 → Description Osmium hexafluoride is a yellow crystalline solid that melts at 33.4 °C and boils at 47.5 °C. The solid structure measured at −140 °C is Orthorhombic crystal system, orthorhombic space group ''Pnma''. Lattice constant, Lattice parameters are ''a'' = 9.387 Angstrom, Å, ''b'' = 8.543 Å, and ''c'' = 4.944 Å. There are four formula units (in this case, discrete molecules) per unit cell, giving a density of 5.09 g·cm−3. The OsF6 molecule itself (the form important for the liquid or gas phase) has octahedral molecular geometry, which has point group (''octahedral symmetry, Oh''). The Os–F bond length i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osmium
Osmium (from Greek grc, ὀσμή, osme, smell, label=none) is a chemical element with the symbol Os and atomic number 76. It is a hard, brittle, bluish-white transition metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element. When experimentally measured using X-ray crystallography, it has a density of . Manufacturers use its alloys with platinum, iridium, and other platinum-group metals to make fountain pen nib tipping, electrical contacts, and in other applications that require extreme durability and hardness. Osmium is among the rarest elements in the Earth's crust, making up only 50 parts per trillion ( ppt). It is estimated to be about 0.6 parts per billion in the universe and is therefore the rarest precious metal. Characteristics Physical properties Osmium has a blue-gray tint and is the densest stable element; it is approximately twice as dense as lead and narrowly denser tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
