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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:       

The 10 Periodic Tables most recently added to the database:

1944   Emerson's Spiral Formulation
2024   Marks' Aufspaltung Formulation
2024   Bilateral Symmetry in the Periodic Binodic Table
2008   Franklyn's Periodic Table
2024   Periodic Table of Food Initiative (PTFI)
1918   One of Mendelejeff's Tables, Modified
2024   Can I Lick It? Periodic Table
2023   Kudan's 3D Model of The Periodic Table
2019   Ossmi LH & Chasib's Periodic Table
1911   Emerson's Periodic Table of Atomic Weights

Year:  1944 PT id = 1305

Emerson's Spiral Formulation

Emerson EI, 1944, A new spiral form of the periodic tableJChemEd., vol. 21, no. 3, pp. 111–115

René Vernon writes:

Emerson says that the elements in the A groups are called the representative elements because, as Eble states, they "include metals, nonmetals, inert elements, liquids, and gases." Eble RL, 1938, Atomic structure and the periodic table, JChemEd., vol. 15, p. 575

Note the inclusion in Emerson’s table of the neutron as element 0. Astonishingly, Emerson writes: "Element 0, possibly neutron [sic], is considered as a noble gas. Because of its probable chemical inertness and extreme density it might not be detected in a sizeable amount until some future scientist succeeds in sampling the center of the Earth." (p. 111)

(Mark Leach adds: The date is 1944 when the Manhattan Project was in full swing and nothing was being published about nuclear physics and/or neutron interactions. This idea may have come from some type of Popular Science story?)

Other features:

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Year:  2024 PT id = 1304

Marks' Aufspaltung Formulation

John Marks' Aufspaltung (or "Splitting") formulation, after Mendeleyev (1869), Ramsay (1915) & Sommerfeld (1916).

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Year:  2024 PT id = 1303

Bilateral Symmetry in the Periodic Binodic Table

René Vernon, who developed these ideas, writes:

This table is adapted from the work of Gutiérrez-Samanez (2020), who discusses mathematising the chemical periodic system as a grid, which leads to a quadratic function or “binódica function” formed by pairs of periods or binodos (dyads).

The difference is that whereas Gutiérrez-Samanez showed the first pair of periods as H-He and Li-Be, this table shows the first period as e-n and H-He. Here, e is the electron and n is the neutron. Each pair of periods is shown pancake style rather than in a single row. The formula for the length of each paired period or binode is 2n2 = 2, 8, 16, 32.

The idea of paired periods has a long history; it seems to have originated with Werner in 1905.

According to Jensen:

"The temptation to read more into the shape of the table than is really there is almost overwhelming. Even someone as great as Werner was tempted (1905). Having postulated a missing element between H and He, he decided to perfect the symmetry of his table by guaranteeing that rows of differing length always occurred in pairs. Consequently, he further postulated a row of three missing elements lying above the H-X-He row."

Rydberg (1913, pp. 12–13) used a formula 4n^2 for the number of elements in the paired periods: 4, 16, 32, 64. This formula is also used by Gutiérrez-Samanez.

Paired periods were also used by Janet (1928), Saz (1931), Achimov (1946) and Baca Mendoza (1953).


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Year:  2008 PT id = 1302

Franklyn's Periodic Table

Franklyn writes on Electronic Orbital Periodicity Mendelevian grouping is only one possible organizational scheme, regardless of the schematic choice. A table is useful only to the extent that it provides easy reference to data and comparison. Most everyone who has considered arranging elements in tabular form has pondered what layout best serves the purpose. Below is a table I once made to determine the electronic shell and orbital structure of any element at a glance. Everything to the left and above the elements position indicates the complete full orbitals for those shells. Actually you can see the goup memebers run diagonally from upper left to lower right This arrangement shows that the progression of successive electrons is not straight forward with regard to placement within the atoms. The Mendelevian sequence begining with period 6 through the Lanthanides back to period 6 transition metals until Radon, continuing with period 7 ending with the first member of the Actinides, is as follows:

Thanks to René Vernon for the tip!

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Year:  2024 PT id = 1301

Periodic Table of Food Initiative (PTFI)

Imagine a world where farmers choose to grow specific foods to combat food insecurity and diet-related chronic diseases using practices that are also good for the planet. A world where people everywhere are enabled to select customized diets that support their vitality. This future harnesses the power of food not only as a solution to hunger, but as an essential resource to support the well-being of communities and the environment.

The Periodic Table of Food Initiative (PTFI) is accelerating this future to empower data-driven solutions to our most pressing food system challenges: climate change, biodiversity loss, and malnutrition.

Visit the website:

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Year:  1918 PT id = 1300

One of Mendelejeff's Tables, Modified

From Smith A 1918, General Chemistry for Colleges, 2nd ed., The Century Co., New York, p. 299

René Vernon writes:

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Year:  2024 PT id = 1299

Can I Lick It? Periodic Table

From Reddit, a "A cool guide to element lickability".

Mark Leach writes:

"I think I would colour calcium yellow as it bubbles hydrogen gas when added to water."

Thanks to René Vernon for the tip!

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Year:  2023 PT id = 1298

Kudan's 3D Model of The Periodic Table

Pavel V. Kudan's 3D model of the Periodic Table from Research Gate and via direct download.

Parvel writes:

"The shape of this 3D model allows to show most important thing – H may be aligned over F-Ts and He may be aligned over Ne-Og without classification of H to group F-Ts or He to group Ne-Og. To see that it is needed only that cylinder to be tough (hard) and flat parts to be flexible with ability to change angle. Than is important because according Mendeleev’s principle, maximum valence is main for grouping elements and it is controversial to have element with maximum valence 2 between elements with maximum valence 8.

"Coloring He as gray in the 3D model just reflex the fact that it goes just before the energy gap, as well as coloring Ne-Og in gray show that they too go just before the energy gaps, which makes He and Ne-Og noble. The main is not coloring, but the ability to align and demonstrate.

"You may also remember that the issue of opening the new IUPAC Group 2 project to discuss He group as a continuation of the IUPAC Group 3 project has already been raised in e-mail correspondence with IUPAC some time ago in protection of our reconstruction of Landau’s geometry of the Periodic table.

"I agree with you that double periodicity is important, but also rearrangements of electronic configurations caused by properties of d-orbitals also must be taken in account. For example, Cu has valences 1 or 2, Zn has valence 2 due to special properties of d-orbitals. The 3D model of the Periodic table separates the ability of d-orbitals to steel electrons from s-orbitals and f-orbitals causing of such effects.

"Also when you will have a copy of the 3D model you will see that it unifies both geometry of the Mendeleev’s Periodic table and geometry of the Janet’s Periodic table. Following anticlockwise you may see Mendeleev’s order while following clockwise you may see Janet’s order. It is similar to having the 3D moles of globe as visual aid for better vision of Mendeleev’s Periodic table and Janet’s Periodic table as flat detailed maps."

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Year:  2019 PT id = 1297

Ossmi LH & Chasib's Periodic Table

By Dr Laith Al- ossmi, Thi-qar University, Iraq: Al Ossmi LH & Chasib K F, A New Method of Elements Arrangement to Reattach the F–Block Elements of Lanthanides and Actinides in the IUPAC's Periodic Table of Elements, Med & Analy Chem Int J, 3, 4,2019, pp 1–18. DOI 10.23880/macij-16000148

The new 3-dimantional layout of the periodic table graphically shows the main body parts of the table and also these vertical and horizontal coordinators of Periods, Groups, and Nadas.

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Year:  1911 PT id = 1296

Emerson's Periodic Table of Atomic Weights

Emerson BK, Helix chemica: A study of the periodic relations of the elements and their graphic representation, American Chemical Journal, vol. 45, pp. 160–210 (1911). The formulation below appears on page 173; a scanned pdf version of the paper can be viewed here.

René Vernon writes:

Emerson includes two elements before hydrogen: "E" (either the luminiferous ether or the electron) and "Coronium". There are also two elements between hydrogen and helium: "Nebulium" and "Protofluorine".

This is the first time I have seen a PT showing four extra elements and where they are supposed to fit.

After La, Emerson incorporates 13 lanthanides (Ce to Lu) as transition elements into his 7th period.

Emerson missed dysprosium, between Tb and Ho.

"A, B and C" at the bottom right are supposed to be 'halogen emanations'.

Mark Leach adds that Emerson's very odd Periodic Table of Atomic Weights does not actually show any atomic weights.

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What is the Periodic Table Showing? Periodicity

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