Dubnium

Dubnium (symbol: Db) is a chemical element with atomic number 105. It is a synthetic element—it does not occur in nature and is created only in particle accelerators, where two atomic nuclei are collided so that they fuse together. It belongs to the transactinide elements that come after the actinoid group.

Dubnium atoms are radioactive and decay rapidly. Their half-life (the time it takes for half of a collection of atoms to transform into other elements) is minutes or less, depending on the isotope. For this reason, researchers always work with extremely small numbers of atoms, sometimes only a single atom.

Discovery and naming

The element was said to have been created by two competing research centers during the Cold War: the Joint Institute for Nuclear Research in Dubna, Russia, and an American group based in Berkeley, California. The two sides proposed different names, and this became part of a dispute known as the Transfermium Wars.

Eventually, the International Union of Pure and Applied Chemistry (IUPAC) decided that the official name should be dubnium, derived from the city of Dubna. Before that decision, names such as unnilpentium (Unp) and hahnium (Ha) had been used.

Chemical properties

According to the periodic table, dubnium is in group 5, in the same period as vanadium, niobium, and tantalum. Its properties are expected to resemble those of tantalum, particularly in its maximum oxidation state of +5. However, relativistic effects on electron behavior could cause it to differ from what the periodic table predicts.

Uses

Dubnium has no industrial or commercial use. It is made only for research purposes, to understand the structure of heavy nuclei and the limits of the periodic table.