title: Beryllium bromide
text: # Beryllium bromide
  
  Beryllium bromide is the chemical compound with the formula $BeBr_2.$ It is very hygroscopic and dissolves well in water. The compound is a polymer with tetrahedral coordinated Be centres.
  
  ## Preparation and reactions
  
  It can be prepared by reacting beryllium metal with elemental bromine at temperatures of 500 °C to 700 °C:
  
      Be + $Br_2$ → $BeBr_2$
  
  Beryllium bromide is also formed when treating beryllium oxide with hydrobromic acid:
  
      BeO + 2 HBr → $BeBr_2$ + $H_2O$
  
  It hydrolyzes slowly in water: $BeBr_2$ + 2 $H_2O$ → 2 HBr + $Be(OH)_2$
  
  ## Structure
  
  Two forms (polymorphs) of $BeBr_2$ are known. Both structures consist of tetrahedral $Be^{2+}$ centers interconnected by doubly bridging bromide ligands. One form consist of edge-sharing polytetrahedra. The other form resembles zinc iodide with interconnected adamantane-like cages.
  
  ## Safety
  
  Beryllium compounds are toxic if inhaled or ingested.
  
  