Mechanical exfoliation WSe2 on sapphire substrate

• CAS: 7440-33-7
• Catalog Number: ACM7440337-12
• Category: Defect-free Single Crystals of Graphene
• Molecular Weight: 183.8g/mol
• Molecular Formula: W
• Description: Dull gray powder or hard, brittle, steel-gray to white metal. Difficult to melt. Mp: 3410°C; bp; 5900°C. Density: 19.3 g/cm³. Used in alloys, light bulb filaments, and cutting tools. Tungsten Dust (for example, from grinding) may present a moderate fire hazard if allowed to accumulate and exposed to an ignition source.;DryPowder; DryPowder, OtherSolid; OtherSolid;GREY-TO-WHITE POWDER.;Physical properties vary depending upon the specific soluble tungsten compound.;Hard, brittle, steel-gray to tin-white solid.
• IUPAC Name: tungsten
• Canonical SMILES: [W]
• InChI: InChI=1S/W
• InChI Key: WFKWXMTUELFFGS-UHFFFAOYSA-N
• Boiling Point: 10701 °F at 760 mm Hg (NIOSH, 2016);5900 °C @ 760 mm Hg;5900 °C;10,701°F
• Melting Point: 6170 °F (NIOSH, 2016);3410 °C;3410 °C;6170°F
• Density: 19.3 (NIOSH, 2016);18.7-19.3 @ 20 °C/4 °C; depends on extent of working.;19.3 g/cm³;19.3
• Solubility: Insoluble (NIOSH, 2016);Sol in mixture of nitric acid and hydrofluoric acid;Solubility in water: none;Insoluble
• Autoignition Temperature: >=100 °C
• Color/Form: Steel-gray to tin-white metal; body centered cubic structure;CRYSTALLINE FORM GRAY-BLACK, CUBIC;Hard, brittle, steel-gray to tin-white solid.
• Complexity: 0
• Covalently-Bonded Unit Count: 1
• EC Number: 231-143-9
• Exact Mass: 183.950933g/mol
• Formal Charge: 0
• H-Bond Acceptor: 0
• H-Bond Donor: 0
• Heat of Vaporization: 1150 cal/g
• Heavy Atom Count: 1
• ICSC Number: 1404
• Monoisotopic Mass: 183.950933g/mol
• Other Experimental: Very pure tungsten can be cut with hacksaw and forged, spun, drawn, and extruded; impure metal brittle, worked with difficulty;NOT AFFECTED BY SULFUR OR PHOSPHORUS; GOOD ELECTRICAL CONDUCTIVITY;VIGOROUS REACTION WITH BROMINE TRIFLUORIDE, CHLORINE TRIFLUORIDE; REACTION WITH FLUORINE MAY BE INCANDESCENT;Corroded by sea water.;Atomic number: 74; valences 6, 5, 4, 3, 2. Naturally occurring isotopes: 180 (0.135%); 182 (26.4%); 183 (14.4%); 184 (30.6%); 186 (28.4%).;Hardness: 6.5-7.5. Specific heat (20 °C): 0.032 cal/g/deg C; heat of fusion: 44 cal/g; electrical resistivity (20 °C) 5.5 uohm-cm.;Forms trioxide at red heat; not attacked by water; oxidized to dioxide by steam; very stable to acids, attacked only superficially by concn nitric acid or aqua regia; attacked by fluorine at room temp; by chlorine at 250-300 °C giving hexachloride in absence of air and trioxide and oxychloride in presence of air.;Powdered tungsten can be pyropohric under the right conditions. Slowly sol in fused potassium hydroxide in air, in fused sodium carbonate in air, and sol in fused mixture of sodium hydroxide and nitrate.
• Rotatable Bond Count: 0
• RTECS Number: YO7175000
• Size: 10 mmx10 mm
• Stability: STABLE IN DRY AIR @ ORDINARY TEMP;OXIDIZES IN AIR & MUST BE PROTECTED @ ELEVATED TEMP
• UNII: V9306CXO6G
• UN Number: 3089;1325
• Vapor Pressure: 0 mm Hg (approx) (NIOSH, 2016);1.97X10-7 mm Hg @ 2,327 °C;0 mmHg (approx)