Periodic Table |
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| What is the Periodic Table Showing? | Periodicity |
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. The database holds information on periodic tables, the discovery of the elements, the elucidation of atomic weights and the discovery of atomic structure (and much, much more).
| Year: 1949 | PT id = 1052, Type = formulation |
Catalán's Periodic System/Sistema Periodico Ampliado
Two versions of Catalán's Periodic System/Sistema Periodico Ampliado. The first from Moore, Charlotte E., Atomic Energy Levels, National Bureau of Standards, Circular no. 467 (Washington, D. C.: U. S. Government Printing Office, 1949), vol. 1, Table 25. and the second as referenced here: http://www.miguelcatalan.net/pdfs/bibliografia/biblio09.pdf.
René Vernon, who provided the graphics, writes:
"I feel the footnote along the base of the first table could merit better attention being drawn to it. It says:
This arrangement is by Catalán. The electrons indicated in column two that are connected by braces have approximately the same binding energy. Consequently, for some elements one type of electron is preferred over another in the normal configuration, as for example, Cr, Cb, Pd, La, Ac, Th.
"The connecting braces hone in on the source of much of the controversy concerning notions of an ideal, optimal, better, this or that, or fundamental periodic table. I can't recall seeing a table with such a feature. For the second table, turning it on its side (attached) reminds of the ADOMAH [formulation].
Click on the images to enlarge:
Thanks to René for the tip!
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| What is the Periodic Table Showing? | Periodicity |
© Mark R. Leach Ph.D. 1999 –
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