The INTERNET Database of Periodic Tables
There are hundreds of periodic tables in web space, but there is only one comprehensive database of periodic tables & periodic system formulations. If you know of an interesting periodic table that is missing, please contact the database curator: Dr Mark R Leach.
Island of Stability
From Wikipedia: The island of stability in nuclear physics describes a set of as-yet undiscovered isotopes of transuranium elements which are theorized to be much more stable than others. The possibility was proposed by Glenn T. Seaborg in the late 1960s: Prospectd for Further Considerable Extension of the Periodic Table, J.Chem.Educ., 46, 626-633 (1969) and reprinted in Modern Alchemy: Selected Papers of Glenn T. Seaborg (1994).
The hypothesis is that the atomic nucleus is built up in "shells" in a manner similar to the structure of the much larger electron shells in atoms. In both cases, shells are just groups of quantum energy levels that are relatively close to each other.
© Mark R. Leach 1999-
Queries, Suggestions, Bugs, Errors, Typos...
If you have any:
This free, open access web book is an ongoing project and your input is appreciated.
counter started in 2011