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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:       

Periodic Tables from the year 1925:

1925   Friend's Periodic Sphere
1925   Noddack's Periodic Table
1925   Deming's (Updated) Periodic Table
1925   Courtines' Model of the Periodic Table or Periodic Classification
1925   Sommerfeld's Electon Filling Diagram
1925   Model of the Periodic System of de Chancourtois

Year:  1925 PT id = 84

Friend's Periodic Sphere

J. A. N. Friend, "The periodic sphere and the position of the rare earth metals", Chem. News., 130, 196-7 (Mar., 1925).

From Quam & Quam's 1934 review paper.pdf

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Year:  1925 PT id = 308

Noddack Periodic Table

Ida Noddack studied the periodic table in the first half of the 20th century and was the co-discoverer of the last non-radioactive element to be isolated, rhenium. Later she worked on nuclear fission. In 1925 presented Noddack her formulation:

From Ida Noddack and the Missing Elements by Fathi Habashi, Education in Chemistry (March 2009)

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Year:  1925 PT id = 460

Deming's (Updated) Periodic Table

This 1925 table has the Heavy Metals spread out, and the Rare Earth Elements (fifteen, including La and Lu) withdrawn into a box that is divorced from the body of the table. Ce, Gd, Yb form a vertical triad.

Th is assigned to Group IV below Hf.

From Michael Laing's paper: A Revised Periodic Table with the Lanthanides Repositioned, Found. Chem. (2005) 7: 203–233

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Year:  1925 PT id = 735

Courtines' Model of the Periodic Table or Periodic Classification

Published in J. Chem. Ed., 2, 2, 107-109 in 1925 by M. Courtines of the Laboratory of Experimental Physics, College of France, Paris.

Q&Q write:

"The unfolded tower arrangement appears much like a modernised Chauvierre chart cut on a line between Ni and Cu, Cu, with the right part fitted to the left in order of increasing atomic numbers. The rare-earth elements, however, are placed on a novel accordion-like folded strip with ends made secure just below Xt and between Ba and Hf. The author describes in detail the method of folding the chart into a tower-like cylindrical model. H is folded back to show its lack of relationship other groups of elements. In the space for each symbol, electron arrangements and isotopes are also enumerated."

From Quam & Quam's 1934 review paper.pdf

And, in what appears to be a 'top down' view of the above 3D formulation, Courtine M 1926, Oùen est la physique, Gauthier-Villars et Cie, Paris:

Thanks to Eric Scerri for the tip & René Vernon's additions!
See the website and Eric's Twitter Feed
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Year:  1925 PT id = 926

Sommerfeld's Electon Filling Diagram

Arnold Sommerfeld diagram appears in an issue of Memoirs and Proceedings of the manchester Literary and Philosophical Society for 1925-26. volume 70, p. 141-151.

Eric Scerri writes:

"The electron groupings are not exactly the same as what is believed to exist today but it amounts to the same order of filling. For example p orbitals were thought to consist of two groups of 2 and 4 electrons, rather than 2, 2, 2 as believed today. Similarly d orbitals were thought to be formed of two groups of 4 and 6 electrons. With that in mind you will see that Sommerfeld was the first to propose an aufbau filling system: The occupation of 4s before 3d or as represented here the 2 electrons in orbit 11 followed by the 4 and 6 from orbits 3,s and 3,3.

"Sommerfeld does indicate sub-shells. They are just not the same groupings as the current ones. For example 2,1 and 2,2 indicates subshells within the 2nd main shell. Similarly the 3rd shell is presented as 3,2 and 3,3. The totals are of course the same, namely 6 for what we now call p orbitals and 10 for what we call d orbitals. All this came before the discovery of the 4th or spin quantum number. This is in keeping with Bohr's original assignment of shells and sub-shells.

"The discovery of sub-structure to electron shells was not an 'all or nothing' development, but a gradual and almost organic evolution."

Eric has a new book out – A Tale of Seven Scientists and a New Philosophy of Science – in which the gradual evolution of electronic structure involving Bohr, Sommerfeld, Bury, Main Smith, Pauli and others is traced out.

Thanks to Eric Scerri for the tip! 
See the website and Eric's Twitter Feed

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Year:  1925 PT id = 1035

Model of the Periodic System of de Chancourtois

From the Science Museum in the UK collection, a model of the Periodic System of de Chancourtois from 1862:

"Model demonstrating the telluric screw periodic system of Alexander-Emile Beguyer de Chancourtois proposed in a paper published in 1862.

"This model, made by the Science Museum in 1925, provides a rare physical realisation of arguably the earliest periodic system of for the elements. It was devised by the French geologist, Alexander-Emile Beguyer de Chancourtois in 1862, 7 years prior to Dmitri Mendeleev's periodic table.

"De Chancourtois arranged the elements in the order of their atomic weights along a helix which was traced on the surface of a vertical cylinder, with an angle of 45 degrees to its axis. The base of the cylinder was divided into 16 equal parts (the atomic weight of oxygen), and the lengths of the spiral corresponding to the weights of the elements were found by taking the one-sixteenth part of a complete turn as a unit":

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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