Periodic Table
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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: 

  Text Search:       

Year:  2022 PT id = 1230

Kudan's Left-Step Periodic Table (Short Form)

From Pavel Kudan, a specialist in mass-spectrometry and identification of compounds., who suggests a short-form variant of his left-step Periodic table:

1. Energy barriers directly shown to express correctly the Periodic Law
2. 4 periods (8 half periods)
3. 21 groups (1a-8a, 2b-8b, 3c-8c)
4. F-elements classified by groups, not families
5. La/Ac and Lu/Lr both in 3rd group
6. Cu/Ag/Au/Rg in group 8b together with Ni/Pd/Pt/Ds
7. Reminders for H to group 7a, He to group 8a, Cu/Ag/Au/Rg to group 1b

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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