All practice pages/Interatomic theory/Elements
Element 60, a lanthanide
The element in the strongest permanent magnets ever made, from earbuds to electric car motors.
Period 6, in the lanthanide row set below the main table. The other lanthanides are tinted, and every cell opens its own article.
Neodymium has 60 electrons, one for every proton, so the atom carries no charge. Below are the same 60 electrons written two ways.
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f⁴ 5s² 5p⁶ 6s²
Short form: [Xe] 4f⁴ 6s², where [Xe] stands for the 54 electrons xenon already has.
That list runs by shell. In the order the subshells fill it reads [Xe] 6s² 4f⁴, because a subshell fills by its energy, not by its shell number.
The simple form counts electrons shell by shell. The orbital form says which subshell each one sits in: s holds 2, p holds 6, d holds 10 and f holds 14. Shell 4 here is 4s² 4p⁶ 4d¹⁰ 4f⁴, and 2 + 6 + 10 + 4 is 22.
Neodymium sits in period 6 and has 6 shells. The period number counts the shells.
The outer shell holds 2 electrons. Those are the ones neodymium can lose, gain or share, so they are the ones that decide what it bonds with.
Like the other lanthanides, it gives up three electrons to form the Nd³⁺ ion in most of its compounds.
Found with the other light rare earths in bastnäsite and monazite, mostly mined and refined in China.
Carl Auer von Welsbach separated it from didymium in 1885, along with praseodymium, and named it from the Greek neos, new, and didymos, twin.
Neodymium-iron-boron magnets, invented in the early 1980s, are the strongest permanent magnets. They run electric car motors, wind turbines, hard drives, speakers, headphones and phone vibration motors. Neodymium also makes Nd:YAG lasers and gives glass a purple color.
Neodymium magnets snap together hard enough to pinch skin badly and shatter, and swallowing two or more can be life-threatening.