13470-20-7

Basic information

• Product Name: uranium tetrabromide
• Synonyms: uranium tetrabromide;Uranium(IV) bromide.;Uran(IV) tetrabromide
• CAS NO: 13470-20-7
• Molecular Formula: Br₄U
• Molecular Weight: 557.64491
• EINECS: 236-734-5
• Mol File: 13470-20-7.mol
• Article Data: 6

Chemical Properties

• Melting Point: 519°C
• Boiling Point: 778.62°C (estimate)
• Flash Point: °C
• Appearance: /brown hygroscopic crystals
• Density: g/cm³
• CAS DataBase Reference: uranium tetrabromide(CAS DataBase Reference)
• NIST Chemistry Reference: uranium tetrabromide(13470-20-7)
• EPA Substance Registry System: uranium tetrabromide(13470-20-7)

Safety Data

• Hazardous Substances Data: 13470-20-7(Hazardous Substances Data)

Usage

Chemical Properties

dark brown, very hygroscopic crystal(s); prepared by heating uranium turnings in a nitrogen gas stream saturated with bromine vapor; can be purified by vacuum distillation in a similar nitrogen stream [KIR83]

InChI:InChI=1/4BrH.U/h4*1H;/q;;;;+4/p-4

Upstream product

• 10035-10-6 hydrogen bromide 
• 10026-10-5 uranium(IV) chloride 
• 558-13-4 carbon tetrabromide 
• 10097-32-2 bromine 
• 7558-02-3 potassium bromide 
• 7726-95-6 bromine 
• 7727-15-3 aluminium bromide 
• 13172-31-1 disulphur dibromide 

Downstream Products

• 13470-19-4 uranium(III) tribromide 
• 10097-32-2 bromine 

Relevant articles and documents

A spatially separated [KBr6]5- anion in the cyanido-bridged uranium(IV) compound [U2(CN)3(NH3)14]5+[KBr6]5-·NH3

The reaction of uranium tetrabromide with potassium cyanide in anhydrous liquid ammonia at room temperature leads to the formation of brown crystals of [U2(CN)3(NH3)14]5+ [KBr6]5- · NH3. We determined the crystal structure of the compound by single crystal X-ray diffraction. To the best of our knowledge it contains the unprecedented spatially separated [KBr6]5- anion and presents the first uranium(IV) cyanide compound which forms a layer structure. The compound crystallizes in the trigonal space group P3 m1 (No. 164) with a = 10.3246(13), c = 8.4255(17) ?, V = 777.8(3) ?3, Z = 1 at T = 100 K and is well described with the Niggli formula 2 ∞[U(CN)3/2(NH3)7/1]2[KBr6/1].

Study of the electronic structure of the actinide tetrabromides ThBr4 and UBr4 using ultraviolet photoelectron spectroscopy and density functional calculations

Ultraviolet photoelectron spectroscopy and density functional theory was used to study the electronic structure of actinide tetrabromides. A high temperature photoelectron spectrometer was used to record photoelectron spectra for ThBr4 and UBr4. Vertical ionization energies were calculated for the tetrahalides and supporting matrix isolation experiments were carried out.

Facile Syntheses of pure Uranium(III) Halides: UF3, UCl3, UBr3, and UI3

Herein we describe a convenient lab scale synthesis for pure and solvent-free binary uranium(III) halides UCl3, UBr3, and UI3. This is achieved by the reduction of the respective uranium(IV) halides with elemental silicon in borosilicate ampoules at moderate temperature. The silicon tetrahalides SiX4 formed as a side product are utilized for the removal of excess starting material via a chemical vapor transport reaction. The syntheses introduced herein avoid the need for pure metallic uranium and are based on uranium(IV) halides synthesized from UO2 and the respective aluminum halides and purified by chemical vapor transport. These uranium(III) halides are obtained in single crystalline form. A similar reaction yields UF3 as a microcrystalline powder. However, no beneficial transport reaction occurs with this halide. Also, a higher temperature has to be applied and steel ampoules have to be used. The identities and purity of the products were checked by powder X-ray diffraction as well as IR spectroscopy. The synthesis of UI3 enabled its crystal structure determination on single crystals for the first time. UI3 crystallizes in the PuBr3 structure type with space group type Cmcm and a = 4.3208(9), b = 13.923(3), c = 9.923(2) ?, V = 596.9(2) ?3, and Z = 4 at T = 100 K.