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The INTERNET Database of Periodic Tables

There are thousands of periodic tables in web space, but this is the only comprehensive database of periodic tables & periodic system formulations. If you know of an interesting periodic table that is missing, please contact the database curator: Mark R. Leach Ph.D.

Use the drop menus below to search & select from the more than 1300 Period Tables in the database: 

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Year:  2006 PT id = 199
Schemata of the Elements

"The conventional periodic table reflects what is called the aufbau design, which represents a progression of numbers; in this case, that of the atomic number of the elements. The table, however, contradicts the aufbau concept in reality, because there are large gaps within among the primary (representative) elements, as well as in relation to the tertiary elements (transition and inner transition elements). The latter case, the Lanthanoids and the Actinoids, lie completely outside of the main body of the periodic table, thereby effectively breaking down the aufbau design... more..." from here by Charles William Johnson:

The Neutronic Schemata: Specialized Schemata of the Elements

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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