Samarium
Name: Samarium
Symbol: Sm
Atomic Number: 62
Mass fraction of the earth’s shell: 6 x 10-4 %
Melting Point: 1072 °C
Boiling Point: 1794 °C
Electrical Conductivity: 1,06 x 106 A·V−1·m−1
Name: Samarium
Symbol: Sm
Atomic Number: 62
Mass fraction of the earth’s shell: 6 x 10-4 %
Melting Point: 1072 °C
Boiling Point: 1794 °C
Electrical Conductivity: 1,06 x 106 A·V−1·m−1
HISTORY
There is some disagreement about who discovered samarium. Various sources mention the Swiss Jean Charles Galissard de Marignac, Marc Delafontaine, and the Frenchman Paul Émile Lecoq de Boisbaudran.
It was De Marignac who spectroscopically detected samarium in 1853. In 1879, Lecoq de Boisbaudran isolated the element from the mineral samarskite. The name was derived from the mineral samarskite, which in turn was discovered by Colonel Samarski-Bychowez. A year earlier, Delafontaine made the same discovery in didymium oxide. In 1881, Delafontaine showed that his isolated element contained another element besides samarium.
Another 22 years would pass before the German chemist Wilhelm Muthmann isolated metallic samarium by electrolysis for the first time in 1903.
CHARACTERISTICS & EXTRACTION
Samarium is hard and silvery shiny. Finely divided, the metal is reactive and self-igniting. If it comes into contact with hot water or diluted mineral acids, hydrogen is formed. Samarium is usually chemically bound. It often occurs in association with the other lanthanides, in the minerals of the samarskite group, the monazite group, or the cerite group.
The special chemical properties of the element are also used in medicine. For example, the isotope 153Samarium is used in combination with a bisphosphonate (lexidronam) to treat bone pain in cancer patients.
Samarium is mainly produced in China. After enriching the ores and separating the lanthanides, samarium oxide is obtained, which is then reduced with calcium or lanthanum. The result is pure samarium, which has some useful properties. It is used in carbon arc lamps for film projection systems and serves as a neutron absorber in nuclear applications. Samarium is also used in stepper motors for quartz clocks, in headphones, sensors, couplings in stirrers, and hard disk drives.
