Actinium: the essentials

Actinium is dangerously radioactive. The chemical behaviour of actinium is similar to that of the rare earths, particularly lanthanum. It is found naturally in uranium ores and actinium is 150 times more radioactive than radium.

actinium
This sample of uraninite contains some about 10-9 grammes of actinium at any one time. Image adapted with permission from Prof James Marshall's (U. North Texas, USA) Walking Tour of the elements CD.

Actinium: historical information

Actinium was discovered by Andre Debierne in 1899 at France. Origin of name: from the Greek word "aktinos" meaning "ray".

Actinium was discovered by Andre Debierne in 1899 and independently by F. Giesel in 1902, both of whom obtained it while working on separation techniques for rare earth oxides.

Actinium around us Read more »

Actinium has no biological role.

Actinium is found naturally in uranium ores such as pitchblende (mostly UO2). A tonne of pitchblende might yield just about 0.1 g of actinium.

Abundances for cobalt in a number of different environments. More abundance data »
Location ppb by weight ppb by atoms Links
Universe (no data) (no data) Chemical elements abundance by weight in the universe on a miniature periodic table spark table
Crustal rocks (no data) (no data) Chemical elements abundance by weight in the earth's crust on a miniature periodic table spark table
Human (no data) ppb by weight (no data) atoms relative to C = 1000000 Chemical elements abundance by weight in humans on a miniature periodic table spark table

Physical properties Read more »

Heat properties Read more »

Crystal structure Read more »

The solid state structure of actinium is: ccp (cubic close-packed).

Actinium: orbital properties Read more »

Actinium atoms have 89 electrons and the shell structure is 2.8.18.32.18.9.2. The ground state electronic configuration of neutral Actinium is [Rn].6d1.7s2 and the term symbol of Actinium is 2D3/2.

Isolation

Isolation: coming soon!

Actinium isotopes Read more »

Table. Stables isotopes of cobalt.
Isotope Mass
/Da
Natural
abund.
(atom %)
Nuclear
spin (I)
Nuclear
magnetic
moment (μ/μN)
nil

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