![]() ![]() Like most other metals in the lanthanide series, neodymium usually only uses three electrons as valence electrons, as afterwards the remaining 4f electrons are strongly bound: this is because the 4f orbitals penetrate the most through the inert xenon core of electrons to the nucleus, followed by 5d and 6s, and this increases with higher ionic charge. ![]() Its 60 electrons are arranged in the configuration 4f 46s 2, of which the six 4f and 6s electrons are valence. ![]() In the periodic table, it appears between the lanthanides praseodymium to its left and the radioactive element promethium to its right, and above the actinide uranium. To make neodymium magnets it is alloyed with iron, which is a ferromagnet. Neodymium is a rare-earth metal that was present in the classical mischmetal at a concentration of about 18%. Neodymium, like most of the lanthanides, is paramagnetic at room temperature and becomes an antiferromagnet upon cooling to 20 K (−253.2 ☌). Neodymium commonly exists in two allotropic forms, with a transformation from a double hexagonal to a body-centered cubic structure taking place at about 863 ☌. Metallic neodymium has a bright, silvery metallic luster. Larger neodymium magnets are used in electric motors with a high power-to-weight ratio (e.g., in hybrid cars) and generators (e.g., aircraft and wind turbine electric generators). These magnets are widely used in products like microphones, professional loudspeakers, in-ear headphones, high-performance hobby DC electric motors, and computer hard disks, where low magnet mass (or volume) or strong magnetic fields are required. Neodymium alloys are used to make high-strength neodymium magnets-a type of powerful permanent magnet. Neodymium is also used with various other substrate crystals, such as yttrium aluminium garnet in the Nd:YAG laser. These lasers have been used in extremely high-power applications, such as experiments in inertial confinement fusion. Neodymium-doped glasses are used in lasers that emit infrared with wavelengths between 10 nanometers. However, this changes with the type of lighting because of the interaction of the sharp light absorption bands of neodymium with ambient light enriched with the sharp visible emission bands of mercury, trivalent europium or terbium. The color of neodymium compounds comes from the Nd 3+ ion and is often a reddish-purple. Neodymium compounds were first commercially used as glass dyes in 1927 and remain a popular additive. Most of the world's commercial neodymium is mined in China, as is the case with many other rare-earth metals. Neodymium is fairly common-about as common as cobalt, nickel, or copper-and is widely distributed in the Earth's crust. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. ![]() It is present in significant quantities in the minerals monazite and bastnäsite. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach, who also discovered praseodymium. It is generally regarded as having one of the most complex spectra of the elements. When oxidized, neodymium reacts quickly producing pink, purple/blue and yellow compounds in the +2, +3 and +4 oxidation states. It is a hard, slightly malleable, silvery metal that quickly tarnishes in air and moisture. It is the fourth member of the lanthanide series and is considered to be one of the rare-earth metals. Neodymium is a chemical element with the symbol Nd and atomic number 60. ![]()
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