 Discovery Information
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| Who: Soviet scientists at the Joint Institute for Nuclear Research |
| When: 1976 |
| Where: Dubna, USSR |
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| Name Origin
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| Named in honor of the Danish physicist Niels Bohr |
| "Bohrium" in different languages. |
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| Sources
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| Synthetically by bombarding Bi204 with heavy nuclei of Cr54.
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| Uses
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| None. |
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| History
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| It was synthesized in 1976 by a Soviet team led by Y. Oganessian at the Joint Institute for Nuclear Research at Dubna, who
produced isotope 261Bh with a half-life of 1-2 ms (later data gave a half life of around 10 ms). They did this by bombarding bismuth-204 with heavy nuclei of chromium-54.
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| In 1981 a German research team led by Peter Armbruster and Gottfried Münzenberg at the Gesellschaft für Schwerionenforschung (Institute for Heavy Ion Research) in Darmstadt, Germany, were also able to confirm the Soviet team's results and produce bohrium, this time the longer-lived Bh-262.
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| There was an element naming controversy as to what the elements from 101 to 109 were to be called; thus IUPAC adopted unnilseptium
as a temporary, systematic element name for this element. In 1994 a committee of IUPAC recommended that element 107 be named
bohrium. While this conforms to the names of other elements honoring individuals, where only the surname is taken, it was
opposed by many who were concerned that it could be confused with boron. Despite this, the name bohrium for element 107 was recognized internationally in 1997.
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| Notes
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| In 1975 Soviet scientists in Dubna were able to synthesize element 107 which then existed for only 2/1000's of a second. Physicists
at the Heavy Ion Research Laboratory in Darmstadt West Germany confirmed this discovery by synthesizing and identifying six
nuclei of the element. In August of 1997 the International Union of Pure and Applied Chemistry announced the official naming of
this element as Bohrium.
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| Bohrium is a synthetic element that is not occur naturally anywhere. |
| The German discoverers at GSI proposed the name Nielsbohrium (symbol Ns) after Niels Bohr. IUPAC are happy to name an element
after Bohr but suggest bohrium (Bh) on the grounds that the first name of a person does not appear in the names of any other
element named after a person. This seems to have been accepted by all concerned.
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| Element 107 was previously known as Unnilseptium; from the latin from "one zero seven". |
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