Tennessine
Tennessine is a synthetic chemical element with the symbol Ts and atomic number 117. It is a superheavy, radioactive element placed in the halogen group, but only a few atoms have been made, so most of its chemistry is predicted rather than observed directly.
What tennessine is
Tennessine is element 117 on the periodic table. It is synthetic, meaning it is made in nuclear laboratories rather than found in usable natural deposits. It is placed below astatine in Group 17, the halogen column, but its extremely heavy nucleus and short-lived isotopes make it very different from familiar halogens such as chlorine or iodine.
How it was made
Tennessine was produced by colliding atomic nuclei in a particle accelerator. Experiments used calcium-48 ions fired at berkelium-249 targets, creating a few atoms of element 117 through nuclear fusion reactions. The new atoms were identified by tracking their radioactive decay chains rather than by collecting a visible sample.
Discovery and name
The discovery involved researchers associated with the Joint Institute for Nuclear Research in Dubna, Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, and other partners. The name tennessine honors Tennessee, where key institutions contributed to the target materials and superheavy-element research. IUPAC approved the name and symbol Ts in 2016.
Why it is hard to study
Tennessine atoms decay quickly, and experiments produce only tiny numbers of atoms. That makes ordinary measurements, such as melting point, density, or bulk chemical reactions, impractical. Researchers infer many properties from nuclear data, periodic trends, relativistic quantum calculations, and comparison with lighter elements.
Halogen or something stranger
Tennessine sits in the halogen group, but superheavy elements can behave unexpectedly because inner electrons move at relativistic speeds and alter chemical behavior. It may not act like a simple heavier iodine or astatine. Some predicted chemistry suggests metallic character and oxidation states that differ from the classic halogen pattern.
Isotopes and decay
Known tennessine isotopes are radioactive and short-lived. They decay through alpha decay and other nuclear processes into daughter nuclei, which continue through decay chains. These chains are central evidence for the element's creation, because each step provides a fingerprint linking the observed particles to the original superheavy atom.
Superheavy elements
Tennessine belongs to the broader study of superheavy elements, where scientists test how far the periodic table can extend and how nuclear stability changes at very high atomic numbers. The work explores the predicted island of stability, a region where some heavy nuclei may live longer than nearby isotopes even if they are still radioactive.
Uses and limits
Tennessine has no practical commercial use. Its value is scientific: it tests nuclear models, improves heavy-element production techniques, and helps researchers understand how the periodic table behaves at its edge. Any future chemistry will depend on producing enough atoms and observing them before they decay.
Why it matters
Tennessine matters because it shows that the periodic table is still an experimental frontier. It connects nuclear physics, accelerator technology, isotope chemistry, international collaboration, and the question of how matter behaves when atoms become extremely heavy and unstable.