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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:  1942 PT id = 521

Seaborg's Periodic Table of 1942

In his Priestly Medal Address, The Periodic Table: Tortuous Path to Man-Made Elements printed in C&EN April 16, 1979 and reprinted in Modern Alchemy: Selected Papers of Glenn T. Seaborg (1994), page 181, Glenn Seaborg describes how the extension of the PT, caused the discovery of the transuranic elements, plutonium and neptunium, resulted in a new "uranide" group.

The formulation below is the working (and at the time top-secret) formulation used by the Manhatten atomic bomb project. The Lawrence Berkeley Laboratory internal reference number for this document is XBL 798-2509.

Like the 1939 formulation, XBL 769-10601, the formulation below erroneously predicts positions for the heaviest elements:

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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