Terbium

Mosander Carl Gustav bw

Xenotim mineralogisches museum bonn

Terbium is a chemical element with the symbol Tb and atomic number 65. It is a silvery-white, rare earth metal that is malleable, ductile, and soft enough to be cut with a knife. Terbium is never found in nature as a free element, but it is contained within many minerals, including cerite, gadolinite, monazite, xenotime, and eutectic. The element is extracted through ion exchange and solvent extraction techniques from these minerals. Terbium was discovered by Swedish chemist Carl Gustaf Mosander in 1843, who detected it as an impurity in yttrium oxide.

Properties

Terbium is a member of the lanthanide series in the periodic table. Its properties are significantly influenced by its electron configuration, which allows for strong magnetic properties. Terbium has a high melting point (1356 °C) and boiling point (3230 °C), which makes it stable at high temperatures. The element has several allotropes and exhibits a bright, silvery luster when freshly prepared.

Applications

Terbium plays a crucial role in various applications due to its unique physical and chemical properties. It is used in solid-state devices, such as in the manufacture of semiconductors and electronic devices. Terbium-doped calcium fluoride, calcium tungstate, and strontium molybdate are materials that are used in solid-state devices. Additionally, terbium is used in fluorescent lamps and color television tubes, where it acts as a phosphorescent material, emitting green light.

One of the most significant uses of terbium is in magneto-optic materials, which are used in the data storage industry. Terbium-iron-garnet layers are utilized in magneto-optical disks for data storage and retrieval. The element's magnetic properties also make it useful in various alloys for the production of electronic and magnetic devices.

Safety

Terbium, like other lanthanides, is considered to have low to moderate toxicity. However, its compounds should be handled with care, as they can be irritating to the skin and eyes. There is limited information on the health effects of terbium, and it is not known to have any biological role in humans or animals.

See also

• Lanthanides
• Rare earth element
• Magnetic materials