Actinium compounds: actinium trichloride

actinium symbol icon

The actinium in actinium trichloride formally is in the oxidation state 3.

Crystal structure of actinium trichloride

Actinium trichloride

  • Formula as often written: AcCl3
  • Hill system formula: Ac1Cl3
  • CAS registry number: [22986-54-5]
  • Formula weight: 333.386
  • Class: chloride


  • actinium trichloride
  • actinium(III) chloride
  • actinium chloride

Physical properties

  • Colour: white
  • Appearance: crystalline solid
  • Melting point: 1051°C (sublimes)
  • Boiling point:
  • Density: 4810 kg m-3


Coming soon...

Element analysis

Element percentages for the elements in actinium trichloride
Element %
Ac 68.10
Cl 31.90


4Ac(OH)3 + 3CCl4 → 4AcCl3 + 3CO2 + 6H2O

Solid state structure

  • Geometry of actinium:
  • Prototypical structure:

Crystal structure of actinium trichloride

Isotope pattern

What follows is the calculated isotope pattern for the AcCl3 unit with the most intense ion set to 100%.

Formula: Ac1Cl3

mass  %
332 100.0 __________________________________________________
333 0.0
334 95.9 ________________________________________________
335 0.0
336 30.7 _______________
337 0.0
338 3.3 __


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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actinium atomic number