- Ytterbium (Yb) is a soft, silvery-white, and fairly ductile rare earth metal with atomic number 70, belonging to the lanthanide series of the periodic table.
- Its electron configuration is [Xe] 4f¹⁴ 6s², and it most commonly forms Yb³⁺ ions as its stable oxidation state, although the +2 state is also well-known and relatively stable for this element. The atomic structure contains seventy protons, typically one hundred and three neutrons in its most abundant isotope, and seventy electrons arranged in six shells.
- Naturally occurring ytterbium consists of seven stable isotopes, with ytterbium-174 (¹⁷⁴Yb) being the most abundant, comprising about 31.8% of the element’s natural composition.
- Ytterbium does not occur in free form in nature but is found in minerals containing other rare earth elements, such as monazite ((Ce,La,Nd,Th)PO₄), xenotime (YPO₄), and gadolinite ((Ce,La,Nd,Y)₂FeBe₂Si₂O₁₀). Its extraction involves complex separation techniques, including solvent extraction and ion-exchange processes. China is the leading producer, with smaller amounts also coming from countries like the USA, Australia, Brazil, and India.
- Ytterbium was discovered in 1878 by Swiss chemist Jean Charles Galissard de Marignac, who separated it from erbium oxide. In 1907, French chemist Georges Urbain further clarified that Marignac’s ytterbium sample contained two elements—ytterbium itself and a new one later named lutetium. The element’s name comes from the Swedish village of Ytterby, a site notable for the discovery of multiple rare earth elements.
- Ytterbium has a range of specialized applications. It is used as a dopant in fiber optic cables and in solid-state lasers, particularly ytterbium-doped fiber lasers that are highly efficient and widely employed in industrial cutting, welding, and drilling. Certain ytterbium isotopes, such as ytterbium-169 (¹⁶⁹Yb), are radioactive and used in portable X-ray sources for medical and industrial imaging. In metallurgy, ytterbium can be added to stainless steel to improve grain refinement and enhance mechanical properties. Ytterbium compounds also find use as catalysts in organic synthesis. Furthermore, ytterbium’s sensitivity to external pressure makes it valuable in high-pressure physics experiments, as it exhibits a measurable change in electrical resistivity under compression.
- Chemically, ytterbium is more reactive than some heavier lanthanides. It oxidizes slowly in air but more rapidly in moist conditions, forming a thin oxide coating. Ytterbium reacts slowly with cold water and more rapidly with hot water to form ytterbium hydroxide and hydrogen gas. It dissolves readily in dilute acids, producing colorless Yb³⁺ salts.
- Biologically, ytterbium has no known essential role in living organisms and is considered to have low toxicity. However, as with all rare earth elements, fine powders and soluble salts should be handled with care to avoid inhalation or ingestion.
- From an environmental standpoint, ytterbium in its natural mineral state is stable and non-hazardous. Environmental concerns are mainly associated with the extraction and processing of rare earth ores, which can produce toxic waste and, in some cases, release naturally occurring radioactive materials.
