Nd3

Nd3, or neodymium(III) ion, is the trivalent cation of the lanthanide neodymium. In compounds it is typically present as Nd3+. The neutral atom has the electron configuration [Xe]4f4 6s2, while loss of three electrons yields the 4f3 configuration for Nd3+. The 4f electrons are shielded by outer shells, which gives Nd3+ relatively sharp, lattice-insensitive optical transitions in the near-infrared.

Nd3+ is a widely used active ion in solid-state lasers and optical amplifiers. The most famous host is Nd:YAG (neodymium-doped yttrium aluminum garnet), which lases near 1064 nm via the 4F3/2 → 4I11/2 transition. Pumping is commonly done with 808 nm diode lasers, promoting Nd3+ to higher levels from which it relaxes to 4F3/2 before emission. Other hosts such as Nd:YVO4, Nd:glass, Nd:GGG, and various fluoride crystals offer different emission wavelengths, bandwidths, and thermal properties. Nd3+ can also emit at around 1330 nm through the 4F3/2 → 4I13/2 transition, depending on the host.

Applications of Nd3+-doped materials extend beyond fundamental lasers to laser amplifiers, tunable sources, and specialized phosphors for illumination and sensing. The ion’s relatively narrow lines and strong infrared emission make it a staple in industrial machining, medical devices, and optical communications components when paired with suitable hosts and pumping schemes.

Chemically, Nd3+ forms oxides such as Nd2O3 and salts like NdCl3 and Nd(NO3)3. In general, neodymium remains in the trivalent state in common solid-state and solution contexts; handling follows standard chemical-safety practices for rare-earth compounds.