Systematic element name

A systematic element name is the temporary name and symbol assigned to newly synthesized and not yet synthesized chemical elements. In chemistry, a transuranic element receives a permanent trivial name and symbol only after its synthesis has been confirmed. In some cases, this has been a protracted and highly political process (see element naming controversy). In order to discuss such elements without ambiguity, the International Union of Pure and Applied Chemistry (IUPAC) uses a set of rules to assign a temporary systematic name and symbol to each such element. This approach to naming originated in the successful development of regular rules for the naming of organic compounds.

The IUPAC rules

The temporary names are derived systematically from the element's atomic number. Each digit is translated to a 'numerical root', according to the table to the right. The roots are concatenated, and the name is completed with the ending "-ium". Some of the roots are Latin and others are Greek; the reason is to avoid two digits starting with the same letter. There are two sandhi rules designed to prevent odd-looking names.
*If "bi" or "tri" is followed by the ending "ium" (i.e. the last digit is 2 or 3), the result is '-bium' or -'trium', not '-biium' or '-triium'.
*If "enn" is followed by "nil" (i.e. the sequence -90- occurs), the result is '-ennil-', not '-ennnil-'.

The systematic symbol is formed by taking the first letter of each root, converting the first to a capital.

The suffix "-ium" overrides traditional chemical suffix rules, thus 117 and 118 are "ununseptium" and "ununoctium", not "ununseptine" and "ununocton".

All elements up to and including atomic number 111 have received permanent trivial names and symbols, so the use of systematic names and symbols is recommended only for elements 112 and above. Therefore in practice, systematic names are just those with 3-letter symbols (or more, theoretically).

:"Note: These examples show conjectured elements. As of 2008, Unbibium, element 122, is the highest element whose existence has been claimed.

External links

* [http://www.apsidium.com/ext_pt/expertab.htm Extended Periodic Table]
* [http://iupac.chemsoc.org/reports/provisional/abstract04/RB-prs310804/Chap3-3.04.pdf The IUPAC recommendation] . Untitled draft, March 2004. (PDF, 143 kB).
* [http://www.apsidium.com/theory/naming.pdf Systematic naming of Elements with Atomic Numbers Greater than 110] (PDF, 41 kB).
*http://media.iupac.org/publications/pac/2002/pdf/7405x0787.pdf