Beryllium difluoride

  • Formula: BeF2
  • Hill system formula: Be1F2
  • CAS registry number: [7787-49-7]
  • Formula weight: 47.009
  • Class: fluoride
  • Colour:
  • Appearance: crystalline solid
  • Melting point: 552°C
  • Boiling point: 1169°C; 800°C
  • Density: 2100 kg m-3

The following are some synonyms of beryllium difluoride:

  • beryllium difluoride
  • beryllium(II) fluoride
  • beryllium fluoride

The oxidation number of beryllium in beryllium difluoride is 2.


Beryllium fluoride can be made by the thermolysis of ammonium beryllium fluoride, (NH4)2BeF4 - a beryylium complex made by the reaction of BeO with NH4F..

(NH4)2BeF4 (heat) → BeF2(s) + 2NH4F(s)

Solid state structure

  • Geometry of beryllium: 4 coordinate: tetrahedral
  • Prototypical structure:

Crystal structure of beryllium difluoride

Element analysis

The table shows element percentages for BeF2 (beryllium difluoride).

Element %
Be 19.17
F 80.83

Isotope pattern for BeF2

The chart below shows the calculated isotope pattern for the formula BeF2 with the most intense ion set to 100%.


The data on these compounds pages are assembled and adapted from the primary literature and several other sources including the following.

  • R.T. Sanderson in Chemical Periodicity, Reinhold, New York, USA, 1960.
  • N.N. Greenwood and A. Earnshaw in Chemistry of the Elements, 2nd edition, Butterworth, UK, 1997.
  • F.A. Cotton, G. Wilkinson, C.A. Murillo, and M. Bochmann, in Advanced Inorganic Chemistry, John Wiley & Sons, 1999.
  • A.F. Trotman-Dickenson, (ed.) in Comprehensive Inorganic Chemistry, Pergamon, Oxford, UK, 1973.
  • R.W.G. Wyckoff, in Crystal Structures, volume 1, Interscience, John Wiley & Sons, 1963.
  • A.R.West in Basic solid state chemistry Chemistry, John Wiley & Sons, 1999.
  • A.F. Wells in Structural inorganic chemistry, 4th edition, Oxford, UK, 1975.
  • J.D.H. Donnay, (ed.) in Crystal data determinative tables, ACA monograph number 5, American Crystallographic Association, USA, 1963.
  • D.R. Lide, (ed.) in Chemical Rubber Company handbook of chemistry and physics, CRC Press, Boca Raton, Florida, USA, 77th edition, 1996.
  • J.W. Mellor in A comprehensive treatise on inorganic and theoretical chemistry, volumes 1-16, Longmans, London, UK, 1922-1937.
  • J.E. Macintyre (ed.) in Dictionary of inorganic compounds, volumes 1-3, Chapman & Hall, London, UK, 1992.

Explore periodic propertes from these links