Dysprosium is a silvery lanthanide metal known for very high magnetic susceptibility and strong neutron absorption; used in high-performance magnets and nuclear control rods.
The ground-state electron configuration of dysprosium is [Xe] 4f10 6s2. In compounds, dysprosium commonly forms Dy3+ ions by losing the two 6s electrons and one 4f electron, resulting in a 4f9 configuration.
The predominant oxidation state is +3 (Dy3+), which forms compounds such as Dy2O3 and DyCl3. Less common states include +2 in certain halides (DyI2) and intermetallic compounds, though they are less stable.
Dysprosium improves the high-temperature performance of permanent magnets such as Nd2Fe14B. Adding small amounts of Dy enhances the coercivity (resistance to demagnetization) while maintaining magnetic strength, making Dy critical in electric vehicle motors, wind turbines, and high-efficiency generators.
Dysprosium is highly paramagnetic at room temperature and becomes ferromagnetic below 85 K and antiferromagnetic below 179 K. Its magnetic moment arises from ten unpaired 4f electrons, making it one of the most magnetic elements known.
Dysprosium has a very high neutron absorption cross-section, especially for thermal neutrons. This makes it ideal for control rods and neutron shields in nuclear reactors. It helps regulate and stabilize nuclear fission reactions efficiently.
Dysprosium tarnishes in air and reacts slowly with water to form hydroxide and hydrogen gas:
\(\mathrm{4\,Dy(s) + 3\,O_2(g) \rightarrow 2\,Dy_2O_3(s)}\)
\(\mathrm{2\,Dy(s) + 6\,H_2O(l) \rightarrow 2\,Dy(OH)_3(s) + 3\,H_2(g)}\)
For protection, metallic Dy is stored under mineral oil or an inert atmosphere.
Key uses of dysprosium include:
Most Dy3+ compounds are pale yellow to yellow-green. The color arises from characteristic 4f–4f electronic transitions that are weakly influenced by the surrounding ligand environment.
Dysprosium is extracted from rare-earth ores such as monazite and bastnäsite. The extraction involves acid leaching followed by solvent extraction and ion exchange to separate Dy from other lanthanides based on small differences in ionic radii and complex formation constants.
Dysprosium and its compounds are considered to have low toxicity. However, as with all rare-earth metals, fine powders can be flammable and irritating to the eyes, skin, or respiratory system. Proper handling, gloves, and fume ventilation are recommended during use.
A simple oxidation reaction of Dy metal in aqueous solution is:
\(\mathrm{Dy(s) \rightarrow Dy^{3+}(aq) + 3e^-}\)
This reaction demonstrates the formation of the stable trivalent ion, which is common in all Dy compounds.