unnilpentium

Temporary name of the chemical element with atomic number 105. It was first synthesized and identified by A. Giorso, M. J. Nurmia, J. A. Harries, K. A. Y. Eskola and P. Escola at Lawrence Radiation Laboratory in Berkeley, California. They proposed the name hahnium (symbol, Ha), honoring the German physicist Otto Hahn. A conflicting claim from Dubna urged the name nielsbohrium. In August 1994 a panel of the International Union of Pure and Applied Chemistry (IUPAC) recommended it be called joliotium, for the French physicist Frederic Joliot-Curie.

In 1997, the IUPAC Commission on Nomenclature of Inorganic Chemistry recommended the name dubnium (symbol, Db), in honor of Dubna, commenting

The discoveries of elements 104 and 105 are contested by Dubna and Berkeley. Both laboratories appear to have made significant contributions, but what has clearly emerged from the submissions, including those from Berkeley and from Darmstadt, is that the Dubna laboratory has played a key role in developing the experimental strategies used in synthesizing several transfermium elements. The Commission recommended that element 105 should be named dubnium in its honour. The Berkeley laboratory has already been similarly recognized on more than one occasion.¹

1. Inorganic Chemistry Division; Commission on Nomenclature of Inorganic Chemistry.
Names and Symbols of Transfermium Elements (IUPAC recommendation 1997)
Pure and Applied Chemistry, vol. 69, no. 12, pages 2471-2473 (1997).

Available on the Web as a pdf file accessible through www.iupac.org/projects/1995/220_30_95.html