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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 1100 Period Tables in the database:

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Lehikoinen's Circular Clock Form

Otto Lehikoinen writes:

"A circular form separating 1s orbital to the center, set it on a wall clock as there are 48 elements of main periods, thus can be used as markers for half hours. Group 4 is centered on noon and group 7 starts the afternoon, to get anions and cations with the same but opposite charge to be beside each other. Thus the noble gases are centered on midnight which is easily remembered by neon (and other noble gas) lights. The minute hand hits the 40 d-block elements giving an accuracy of 1.5 minutes and seconds could be read from lanthanides and actinides."

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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