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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 = 1078

Demers' Système du Québécium

Updated from this 2002 entry comes: Quebec System, Numbers and geometry in the classification of the elements by Pierre Demers.

Demers writes:

"First, I present the Periodic Table of Elements, and I proceed to improve it. By an arithmetic and geometrical analysis, I make appear important symmetries of order four which exist in the arrangement of the atoms between them. I confirm these results with an original discussion of irregular atoms. I will try, in a work that will follow, to interpret the symmetries of the classification by the symmetries of the atom which are associated with the precession cones of the kinetic moments and orbitals."

Read [much] more on this page of links:



Thanks to Conal for the tip!

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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