Samarium is a metallic element with the chemical symbol Sm and atomic number 62. Samarium is a medium-hard silvery-white metal that oxidizes easily in air. As a typical lanthanide element, samarium usually has an oxidation state of +3. Compounds of samarium (II), the most common are SmO, SmS, SmSe, and SmTe. Samarium has no significant biological effect and is only mildly toxic. Samarium is one of the lanthanides (rare earth elements) that perplexed chemists in the 19th century. Its history began with the discovery of cerium in 1803.

Cerium was presumed to contain other metals, and in 1839 Carl Mosander claimed to have obtained lanthanum and didymium from it. However, didymium is actually a mixture of praseodymium and neodymium. In 1879, Paul Emile Lecoq de Boisbaudran again extracted didymium from yttriobite, after which he prepared a solution of didymium nitrate and added ammonium hydroxide, and found that the precipitate formed in two stages. He measured the spectrum of the first precipitate and concluded that it was a new element, samarium. (Europium was discovered in samarium in 1901.)
 

Chinese name: Samarium [Shularn][shan]

Samarium stick

English name :Samarium

Samarium powder mesh;

CAS:7440-19-9 [2]

EINECS:231-128-7

Molecular formula :Sm

Molecular weight :150.36

Element type: Metal

Atomic volume: 19.95 (cubic cm/mole)

Element content in the Sun: 0.001 (ppm)

Element content in seawater: 0.0000004 (ppm) Pacific surface

Content in the crust: 7.9 (ppm)

Crystal structure: The cell is trisclinal cell.

Oxidation state:

Main Sm+3

Other Sm+2

Vickers Hardness: 412MPa

Velocity of sound propagation in it: 2130 (m/S)

Outer electron shell configuration: 4f6 6s2

Electron shell: K-L-M-N-O-P

Ionization energy (kJ/mol)

M - M+ 543.3

M+ - M2+ 1068

M2+ - M3+ 2260

M3+ - M4+ 3990

Cell parameters:

a = 362.1 pmb = 362.1 pm

c = 2625 pm

Alpha is equal to 90 degrees

Beta = 90°

Gamma is equal to 120 degrees

It is prepared by ion exchange separation from other rare earth elements. It may also be prepared from samarium oxide by reduction of barium or lanthanum.

Physical properties edit broadcast

Metallic samarium

Metallic samarium

It is quite stable in dry air and forms an oxide film on the surface in moist air. It will not decompose if used and stored according to specifications. Avoid contact with acid, oxide and moisture. Soluble in acid, insoluble in water. Easy to combine with non-metallic elements. The fine powder will spontaneously   Occurs in nature as salt of samarium trivalent. It can be used as neutron absorber, photoelectric equipment and alloy manufacturing.
 

Samarium stick application field editor broadcast

Used in the manufacture of laser materials, microwave and infrared equipment, in the atomic energy industry also has a more important use.

Used in electronics and ceramics industry. Samarium is easily magnetized but hard to demagnetize, which means it will have important applications in solid-state components and superconducting technologies in the future.

Since Mosandel's discovery of lanthanum, erbium and terbium, chemists around the world have paid special attention to separating new elements from the discovered rare earth elements. In 1878, the French spectrographer and chemist De la Fontene discovered a new element called decipium from the element known as didymium, which had been discovered by Mosandel. But in 1879, another French chemist, Boisbaudronli, used spectroscopic analysis to determine decipium as a mixture of unknown and known rare earth elements, from which he isolated a new element that was unknown at the time and named it samarium, the element symbol Sm, or samarium.

Samarium and the subsequent discoveries of gadolinium, praseodymium, and neodymium were isolated from didymium, which was then considered a rare earth element. As a result of their discovery, didymium is no longer retained. And it was their discovery that opened the door to the third stage of the discovery of rare earth elements. But this is only half of the third phase. The other half will be the opening of the gate or the separation of yttrium.