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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.

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Year:  1920 PT id = 1112

Pfeiffer's Periodic System of the Elements

V. P. Pfeiffer, Naturwiss. 8, 984-991 (1920), Die Befruchtung der Chemie durch die Röntgenstrahlenphysik (The fertilization of chemistry by X-ray physics).

Yoshi Maeno of Kyoto University writes:

"The question who it was who paved the way to the modern representation of the long-period periodic table is a subject of discussion. In my understanding, it was Alfred Werner in 1905. It is a pity that his invention is sometimes over criticised due to some errors in the placements and orders of some elements in his original work.

"It is much less known who first proposed the familiar form of the long-period table with the rare-earth elements as a separate table placed below the main table for convenience. It is most probably Von Paul Pfeiffer in 1920, below. In his paper, he followed Werner's work and extended the table incorporating the knowledge from X-ray physics. Pfeiffer's table preceded Deming's 1923 table and is more similar to today's standard table.

"Pfeiffer was a student and assistant of Werner at Univ Zurich (Wikipedia).

"I acknowledge Y. Hisamatsu who gave me the information of Pfeiffer's original paper."

Thanks to Yoshi Maeno of Kyoto University for the tip!

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