Magnesium compounds: magnesium dichloride

magnesium symbol icon

The magnesium in magnesium dichloride formally is in the oxidation state 2.

Crystal structure of magnesium dichloride

Magnesium dichloride

  • Formula as often written: MgCl2
  • Hill system formula: Cl2Mg1
  • CAS registry number: [7786-30-3]
  • Formula weight: 95.21
  • Class: chloride


  • magnesium dichloride
  • magnesium(II) chloride
  • magnesium chloride

Physical properties

  • Colour: white
  • Appearance: crystalline solid
  • Melting point: 714°C
  • Boiling point: 1412°C
  • Density: 2325°C


Coming soon...

Element analysis

Element percentages for the elements in magnesium dichloride
Element %
Cl 74.47
Mg 25.53


Not available

Solid state structure

  • Geometry of magnesium:
  • Prototypical structure: CdCl2

Crystal structure of magnesium dichloride

Isotope pattern

What follows is the calculated isotope pattern for the MgCl2 unit with the most intense ion set to 100%.

Formula: Mg1Cl2

mass  %
 94 100.0 __________________________________________________
95 12.7 ______
96 77.9 _______________________________________
97 8.1 ____
98 19.1 __________
99 1.3 _
100 1.4 _


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.

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magnesium atomic number