Gadolinium.

Chemical composition

The chemical composition of gadolinite is unstable - the content of the main components, especially FeO, varies greatly. Basically, gadolinite consists of silicates, cerium, lanthanum, neodymium, yttrium, beryllium and iron. It also contains thorium, less often uranium. Gadolinite formulas: (Ce, La, Nd, Y)2FeBe2Si2O10 or Be2Y2FeII(SiO4)2O2 {Ca, La, Mg, Re, Sc, Th}.

Gadolinium (Gd) Chemical element III of the Mendeleev table. Refers to rare earth metals (part of the yttrium subgroup of lanthanides). Opened in 1880 by J. de Marignac and named after the Finnish chemist J. Gadolin.

Light, slightly oxidized in air metal. With respect to acids and other reagents behaves in the same way as lanthanum and cerium. Gadolinium is characterized by the highest cross-section of thermal neutron capture among all elements. It has the maximum electric resistance compared to all other lanthanides. Magnetic properties put gadolinium on a par with iron, cobalt and nickel.

Gadolinium is slowly oxidized in air at room temperature, above 100 ° C - quickly. Metallic gadolinium reacts with halogens, nitrogen, hydrogen when heated. With prolonged storage in the open air, it gradually dims, covering with an oxide film.

The content in the earth's crust is 5.4 × 10-4 %, in sea water 6 × 10-7 mg / l. Gadolinium is part of the minerals gadolinite, xenothym, monacite, apatite, bastnezite and others.

Use of gadolinium:

• obtaining ultra-low temperatures;
• is part of superconducting ceramics;
• production of cathodes of electronic guns;
• ultraviolet laser;
• production of metal hydrides for hydrogen storage;
• used as a radiation source in medicine for the diagnosis of osteoporosis;
• storage of radioactive waste;
• production of radioisotope energy sources;
• production of special titanium alloys;
• radioisotope energy sources.

Gadolinium metal is quite expensive (more expensive than silver), but still cheaper than europium, terbium.