Beryllium bromide

Beryllium bromide
Names
	IUPAC name Beryllium bromide
Identifiers
CAS Number	7787-46-4 [ECHA];
3D model (JSmol)	Interactive image;
ChemSpider	74208 ;
ECHA InfoCard	100.029.196
EC Number	232-115-9;
PubChem CID	82230;
UNII	T00751H2J8;
CompTox Dashboard (EPA)	DTXSID80999064 ;
	InChI InChI=1S/Be.2BrH/h;21H/q+2;;/p-2 Key: PBKYCFJFZMEFRS-UHFFFAOYSA-L ; InChI=1/Be.2BrH/h;21H/q+2;;/p-2 Key: PBKYCFJFZMEFRS-NUQVWONBAJ;
	SMILES Br[Be-2](Br)([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1([Br+]1)[Br+][Be-2]1(Br)Br;
Properties
Chemical formula	BeBr2
Molar mass	168.820 g/mol
Appearance	colorless white crystals
Density	3.465 g/cm3 (20 °C)
Melting point	508 °C (946 °F; 781 K)sublimes at 473 °C (883 °F; 746 K)
Boiling point	520 °C (968 °F; 793 K)
Solubility in water	Highly
Solubility	soluble in ethanol, diethyl ether, pyridine ; insoluble in benzene
Structure
Crystal structure	Orthorhombic
Thermochemistry
Heat capacity (C)	0.4111 J/g K
Std molar; entropy (S⦵298)	9.5395 J/K
Std enthalpy of; formation (ΔfH⦵298)	-2.094 kJ/g
Hazards
	Occupational safety and health (OHS/OSH):
Main hazards	see Berylliosis
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H315, H317, H319, H330, H335, H350i, H372, H411
Precautionary statements	P260, P301+P310, P304+P340, P305+P351+P338, P320, P330, P405, P501
NFPA 704 (fire diamond)	4 0 0
	NIOSH (US health exposure limits):
PEL (Permissible)	TWA 0.002 mg/m3; C 0.005 mg/m3 (30 minutes), with a maximum peak of 0.025 mg/m3 (as Be)
REL (Recommended)	Ca C 0.0005 mg/m3 (as Be)
IDLH (Immediate danger)	Ca [4 mg/m3 (as Be)]
Related compounds
Other anions	Beryllium fluoride; Beryllium chloride; Beryllium iodide
Other cations	Magnesium bromide; Calcium bromide; Strontium bromide; Barium bromide; Radium bromide
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Beryllium bromide is the chemical compound with the formula BeBr₂. It is very hygroscopic and dissolves well in water. The Be²⁺ cation, which is relevant to BeBr₂, is characterized by the highest known charge density (Z/r = 6.45), making it one of the hardest cations and a very strong Lewis acid.^[3]

Preparation and reactions

It can be prepared by reacting beryllium metal with elemental bromine at temperatures of 500 °C to 700 °C:^[1]

Be + Br₂ → BeBr₂

When the oxidation is conducted on an ether suspension, one obtains colorless dietherate:^[4]

Be + Br₂ + 2 O(C₂H₅)₂ → BeBr₂(O(C₂H₅)₂)₂

The same dietherate is obtained by suspending beryllium dibromide in diethyl ether:^[5]

BeBr₂ 2 O(C₂H₅)₂ → BeBr₂(O(C₂H₅)₂)₂

This ether ligand can be displaced by other Lewis bases.is ether ligand can be displaced by other Lewis bases.

Beryllium bromide hydrolyzes slowly in water: BeBr₂ + 2 H₂O → 2 HBr + Be(OH)₂

Structure

Two forms (polymorphs) of BeBr₂ are known. Both structures consist of tetrahedral Be²⁺ 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.^[6]^[7]

Safety

Beryllium compounds are toxic if inhaled or ingested.

References

^ ^a ^b ^c Perry, Dale L.; Phillips, Sidney L. (1995), Handbook of Inorganic Compounds, CRC Press, pp. 61–62, ISBN 0-8493-8671-3, retrieved 2007-12-10
^ ^a ^b ^c NIOSH Pocket Guide to Chemical Hazards. "#0054". National Institute for Occupational Safety and Health (NIOSH).
^ Buchner, M. R. (2017-01-01), "Beryllium Chemistry", Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, Elsevier, ISBN 978-0-12-409547-2, retrieved 2022-10-27
^ Paparo, Albert; Jones, Cameron (2019-02-01). "Beryllium Halide Complexes Incorporating Neutral or Anionic Ligands: Potential Precursors for Beryllium Chemistry". Chemistry: An Asian Journal. 14 (3): 486–490. doi:10.1002/asia.201801800. ISSN 1861-4728. PMID 30604490. S2CID 58632466.
^ Paparo, Albert; Jones, Cameron (2019-02-01). "Beryllium Halide Complexes Incorporating Neutral or Anionic Ligands: Potential Precursors for Beryllium Chemistry". Chemistry: An Asian Journal. 14 (3): 486–490. doi:10.1002/asia.201801800. ISSN 1861-4728. PMID 30604490. S2CID 58632466.
^ Buchner, Magnus R.; Dankert, Fabian; Spang, Nils; Pielnhofer, Florian; von Hänisch, Carsten (2020). "A Second Modification of Beryllium Bromide: β-BeBr₂". Inorganic Chemistry. 59 (23): 16783–16788. doi:10.1021/acs.inorgchem.0c02832. PMID 33185106. S2CID 226850424.
^ Troyanov, S. I. (2000). "Crystal Modifications of Beryllium Dihalides BeCl₂, BeBr₂, and BeI₂". Zhurnal Neorganicheskoi Khimii. 45: 1619-1624.

[hand-1] Perry, Dale L.; Phillips, Sidney L. (1995), Handbook of Inorganic Compounds, CRC Press, pp. 61–62, ISBN 0-8493-8671-3, retrieved 2007-12-10

[PGCH-2] NIOSH Pocket Guide to Chemical Hazards. "#0054". National Institute for Occupational Safety and Health (NIOSH).

[3] Buchner, M. R. (2017-01-01), "Beryllium Chemistry", Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, Elsevier, ISBN 978-0-12-409547-2, retrieved 2022-10-27

[4] Paparo, Albert; Jones, Cameron (2019-02-01). "Beryllium Halide Complexes Incorporating Neutral or Anionic Ligands: Potential Precursors for Beryllium Chemistry". Chemistry: An Asian Journal. 14 (3): 486–490. doi:10.1002/asia.201801800. ISSN 1861-4728. PMID 30604490. S2CID 58632466.

[5] Paparo, Albert; Jones, Cameron (2019-02-01). "Beryllium Halide Complexes Incorporating Neutral or Anionic Ligands: Potential Precursors for Beryllium Chemistry". Chemistry: An Asian Journal. 14 (3): 486–490. doi:10.1002/asia.201801800. ISSN 1861-4728. PMID 30604490. S2CID 58632466.

[6] Buchner, Magnus R.; Dankert, Fabian; Spang, Nils; Pielnhofer, Florian; von Hänisch, Carsten (2020). "A Second Modification of Beryllium Bromide: β-BeBr₂". Inorganic Chemistry. 59 (23): 16783–16788. doi:10.1021/acs.inorgchem.0c02832. PMID 33185106. S2CID 226850424.

[7] Troyanov, S. I. (2000). "Crystal Modifications of Beryllium Dihalides BeCl₂, BeBr₂, and BeI₂". Zhurnal Neorganicheskoi Khimii. 45: 1619-1624.

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