Neodymium
Neodymium is a chemical element with symbol Nd and atomic number 60. It is a soft silvery metal that tarnishes in air. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach.
Identity
- Atomic mass
- 144.242 u
- Category
- Lanthanides
- Group
- 3
- Period
- 6
- Block
- f
- Oxidation States
- +3
- Phase (25 °C)
- Solid
- Appearance
- silvery white
Electronic Structure
- Electron configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f4
- Short configuration
- [Xe] 4f4 6s2
- Electrons per shell
- 2, 8, 18, 22, 8, 2
- Electronegativity (Pauling)
- 1.14
- Electron affinity
- 185 kJ/mol
- 1st ionization energy
- 533 kJ/mol
- Ionization energies
- 533 · 1040 · 2130 · 3900 kJ/mol
Physical properties
- Melting point
- 1023.9 °C (1297 K)
- Boiling point
- 3073.8 °C (3347 K)
- Density
- 7.01 g/cm³
- Molar heat capacity
- 27.4 J/(mol·K)
Chemical behavior of neodymium
Neodymium has six outer electrons ([Xe] 4f⁴ 6s²) and almost always acts as +3, with a very low electronegativity (1.14). It forms highly ionic bonds and violet-colored salts. It is ferromagnetic in alloy: its four unpaired f electrons generate the magnetic moment that, combined with iron and boron, produces the most powerful permanent magnets. It oxidizes rapidly in moist air.
Reactivity
4 Nd + 3 O₂ → 2 Nd₂O₃
In moist air it tarnishes and flakes quickly, which is why magnets are coated with nickel or epoxy. When heated, it burns to a violet oxide.
2 Nd + 6 H₂O → 2 Nd(OH)₃ + 3 H₂
It reacts with water releasing hydrogen and forming the hydroxide. Corrosion advances if the magnet's protective coating is damaged.
2 Nd + 6 HCl → 2 NdCl₃ + 3 H₂
It dissolves in acids giving violet neodymium(III) salts. The chloride is the raw material for obtaining the metal by electrolysis.
2 Nd + 3 Cl₂ → 2 NdCl₃
With halogens it gives trihalides on heating. With hydrogen it forms brittle hydrides, an intermediate step in magnet recycling by decrepitation.
Notable compounds
| Compound | Formula | Use or importance |
|---|---|---|
| Neodymium magnet | Nd₂Fe₁₄B | Motors, wind power and electronics |
| Neodymium oxide | Nd₂O₃ | Violet glasses and catalysts |
| Neodymium chloride | NdCl₃ | Production of the metal by electrolysis |
| Nd:YAG garnet | Nd:Y₃Al₅O₁₂ | Cutting and medical lasers |
| Neodymium fluoride | NdF₃ | Laser crystals and optical fiber |
Electron shell distribution
View in the atom builderIsotopes
Natural neodymium combines seven isotopes: neodymium-142 (¹⁴²Nd, ~27.2%), ¹⁴³Nd (~12.2%), ¹⁴⁴Nd (~23.8%), ¹⁴⁵Nd (~8.3%), ¹⁴⁶Nd (~17.2%), ¹⁴⁸Nd (~5.7%) and ¹⁵⁰Nd (~5.6%), all with 60 protons. ¹⁴⁴Nd is a primordial radionuclide with an extremely long half-life, and the ¹⁴³Nd/¹⁴⁴Nd pair is used to date rocks and the evolution of the Earth's mantle.
Occurrence and production
It is relatively abundant, at about 41 ppm, in bastnasite and monazite alongside cerium and lanthanum. The main deposits are in China, the United States and Australia, with new projects in Greenland and Africa. It is obtained by acid dissolution, high-purity solvent extraction and electrolysis of molten chlorides or oxides for magnet-grade metal.
History and origin of the name
Carl Auer von Welsbach separated it in 1885 from didymium and named it neodymium, from the Greek neos (new) and didymos (twin): the new twin of praseodymium. Didymium had been believed to be an element since 1841. Its moment came in the 1980s, when Sagawa and Croat invented the Nd₂Fe₁₄B magnet almost simultaneously.
Applications and relevance of neodymium
Uses of the element
As an Nd₂Fe₁₄B alloy it forms the most powerful permanent magnets: headphones, hard drives, electric-vehicle motors, wind generators, clasps and tools. It allows speakers and sensors to be miniaturized without losing magnetic strength.
Uses of its compounds
Neodymium-doped yttrium aluminium garnet (Nd:YAG) is the most widespread cutting, welding and medical laser. The oxide tints glasses and enamels and, with cerium, catalyzes; high-purity salts feed the manufacture of sintered and bonded magnets.
Health, safety and environment
Biological role
It has no biological function and its digestive absorption is minimal. Coated magnets do not release neodymium in normal use; the relevant exposure is occupational, to machining dust.
Safety
The main hazard is mechanical: powerful magnets that trap fingers, break small bones or launch fragments on impact. Small ingested magnets can perforate the intestine as they attract each other. Metal dust is flammable and requires extraction and anti-corrosion coating.
Environment
Mining and separation consume energy and reagents and generate thorium-bearing waste that must be confined. In return, every kilogram in a wind turbine or electric motor avoids tonnes of CO₂. The EU already requires design for dismantling and recycling of magnets in wind power and vehicles.
Frequently asked questions about Neodymium
Why are neodymium magnets so powerful?
Neodymium magnets, made from an alloy of neodymium, iron and boron, generate a very intense magnetic field in a small size. Their power comes from the atomic structure of neodymium, which allows the material to retain a strong permanent magnetization. Because of this, a small magnet can hold surprisingly heavy objects. This ratio of size to strength has made them the most widely used permanent magnet in electronics, motors, speakers and tools.
What products contain neodymium magnets?
Neodymium magnets are present in many everyday and technological products: headphones, speakers, hard drives, phones, sensors, locks, clamping tools, electric motors and wind generators. They are also used in decorative magnets, handbag clasps and magnetic accessories. Their advantage is that they offer high magnetic force without needing great volume, allowing more compact, lighter and more efficient devices.
Why are neodymium magnets coated?
Neodymium is a reactive metal and the alloy used in magnets can oxidize easily, especially in humid environments. That is why magnets usually carry coatings of nickel, zinc, epoxy or other protective materials. Besides preventing corrosion, the coating improves wear resistance and makes handling easier. Without this protection the surface could degrade, weakening the magnet and affecting its performance over time.
What is the difference between neodymium and ferrite magnets?
Neodymium magnets are far more powerful than ferrite magnets of the same size, which allows the weight and volume of motors, speakers and sensors to be reduced. However, they are more expensive, more brittle and more sensitive to corrosion and heat. Ferrite magnets are less powerful but cheap, stable and resistant to oxidation. The choice depends on the balance required between magnetic force, cost, temperature and durability.
Are neodymium magnets dangerous?
Neodymium magnets are safe if handled properly, but can be dangerous because of their great strength. They can trap fingers or skin between two pieces, break on impact and launch sharp fragments. Small magnets pose a serious risk if a child swallows them, because they can attract each other inside the digestive tract. They should also be kept away from pacemakers, magnetic cards, hard drives and other sensitive devices.
Can a neodymium magnet lose its strength?
Yes. A neodymium magnet can lose its magnetization if exposed to temperatures above its working limit, to very intense external magnetic fields, to corrosion or to impacts that damage its structure. Moisture can also degrade the protective coating and promote oxidation of the inner material. Under normal conditions, without excessive heat or impacts, it keeps its magnetism for many years.
Where does neodymium come from?
Neodymium is obtained from rare-earth minerals such as bastnasite and monazite, where it appears alongside cerium, praseodymium, lanthanum and other lanthanides. After the ore is extracted, chemical separation processes —such as solvent extraction— are used to obtain high-purity neodymium compounds. These can then be turned into metal or oxide, the raw material for manufacturing permanent magnets.
Main sources consulted: PubChem, Royal Society of Chemistry, NIST, IUPAC. Last revision: November 2026.