Cuprous Bromide




Cuprous bromide is also known as copper (I) bromide is a chemical compound. CuBr is the chemical formula of cuprous bromide. Cuprous bromide (solid) is diamagnetic. It espouses a polymeric chemical structure, which is the same that of zinc sulfide. 
Chemical structure of cuprous bromide 


Cuprous bromide coordinates to form Cu4Br4 Cubane Tetramer. Cuprous bromide is a face-centered cubic consisting of anions and cations occupying ½ of the holes (tetrahedral holes).Every ion is a 4-coordinate and has a local tetrahedral geometry.


Figure 1: Red balls represent Cu- while the blue balls denote Br-.Copper ions occupy only one-half of the holes (tetrahedral holes).



Figure 2: Yellow balls represent Br- ions while slate blue balls represent copper ions. As in Figure 1, copper ions occupy one-half of the tetrahedral holes.


Characteristics of cuprous bromide
·         Cuprous bromide is colorless. However, its samples are always colored as a result of the existence of copper (II) contamination. 

·         It readily oxidizes in the air.

·         It does not dissolve in various solvents. This is because of its polymeric structure. 

·         Treating cuprous bromide with Lewis bases converts it to a molecular adduct. For instance, when it is reacted with dimethyl sulfide leads to the formation of a colorless coordination complex as shown: 

CuBr + S (CH3)2= CuBr(S (CH3)2)

·         When cuprous bromide vapor is thermally excited it produces a blue-violet emission.

Preparation of cuprous bromide
Cuprous bromide is synthesized by reducing copper salts with sulfite in the vicinity of bromide. For example, the chemical equation below shows copper (II) bromide to produce target compound (copper (I) bromide) and a by-product (hydrogen bromide). 

2 CuBr + H2O + SO32-=2 CuBr + SO42- + 2 HBr
Uses of cuprous bromide
·         It is used in the manufacturing of organic compounds.  

·         Other CuBr complexes are used as catalysts for CDC (Cu-catalyzed Cross-dehydrogenative coupling). Additionally, they catalyze Atom Transfer Radical Polymerization. 

·         It is applied in copper bromide lasers as a lasing medium. 

For further reading, I recommend these books: 
1) Inorganic Chemistry 6th Edition by Shriver, Weller, Overton, Armstrong, and Rourke
2) Inorganic Chemistry(5 Edition) By Miessler, Fischer, and Tarr
3) Inorganic Chemistry For Dummies 1st Edition By Matson and Orbaek

Comments

  1. alfachemistry14 March 2019 at 08:19

    We also provide analytical services and laboratory services to our customers. N-butyl-3-metylpyridinium bromide

    ReplyDelete

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