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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 1100 Period Tables in the database:

  Text Search:       

The 10 Periodic Tables most recently added to the database:

1930   Gardner's Table of Electronic Configurations of the Elements
1958   Weaver & Foster's Laminar Chart of the Elements
1940   Hsueh & Chiang's Periodic Properties of the Elements
2018   Kurushkin's 32-Column Periodic Table & Left-step Periodic Table United
1918   Cherkesov: Two Periodic Tables
2022   Deming's 1923 Periodic Table, Updated by Vernon
1984   Cherkesov: Two Periodic Tables
2022   Tutti Frutti Periodic Table
1923   Deming's Periodic Table With Commentry by Vernon
1954   Ephraim's Periodic Classification


Gardner's Table of Electronic Configurations of the Elements

A table of electronic configurations of the elements. Nature 125, 146 (1930).


"MR. ROY GARDNER gave an interesting paper on A Method of Setting out the Classification of the Elements at a recent meeting of the New Zealand Institute. The paper included the accompanying Table, which shows the distribution of electrons into groups corresponding to the principal quantum numbers for all the elements and at the same time preserves the most essential features of the two-dimensional arrangement of Mendeleef. Elements having the same complete groups (that is, all stable groups of 8 or 18) are placed in the same horizontal row, and the vertical columns include elements with the same number of electrons in the incomplete outer groups. The electronic configurations are those given by Sidgwick ("Electronic Theory of Valency", 1927). An asterisk marks elements for which the 'normal' atom is thought to have only one electron in the outermost group, but as practically all these give divalent ions, the point is of minor interest chemically. Distribution of electrons into k-subgroups is unnecessary; these have at present little significance for chemical purposes, and in any case the subgroups are considered to be filled in order to the maxima 2, 6, and 10."

René Vernon writes:

In this table Gardner emphasises the existence of four types of elements:

    1. those with all "groups" complete
    2. those with one incomplete group
    3. those with two incomplete groups (transition elements)
    4. those with three incomplete groups (rare earth elements)

The upper limits of existence of covalencies of 8, 6, and 4 are marked by heavy horizontal lines.


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Weaver & Foster's Laminar Chart of the Elements

Weaver EC & Foster LS 1960, Chemistry For Our Times. 3rd ed., McGraw-Hill, New York, p. 382

René Vernon writes:

An earlier version of this table appeared in JChemEd in 1949. The authors then wrote:

"It is apparently difficult to give a proper idea of electronic configuration in two dimensions without spreading out vertically or horizontally, and thereby sacrificing the order of atomic number, or compactness, or both. In three dimensions it is entirely feasible, but the first reaction is to discard three dimensions as too awkward. The laminar chart here proposed seems to the authors to possess the advantages of both the two dimensional and three dimensional charts and to have none of their disadvantages.

"A minor feature of the table, introduced for reasons of expediency, is the artificial break between the first and the second main shell. Use is made of this space to print the traditional group headings, I A, III A, IVB, etc., which are firmly entrenched in the literature, and still find active use as classifying labels. Other objects in making the artificial break were to minimize the resemblance between hydrogen and the alkali metals and to emphasize helium's character as an inert gas (completed 1s subshell), rather than, as might otherwise be supposed, a member of the alkaline earth family.


"By another modification, constructing the Periodic Chart in the form of contour laminae, it is possible to represent actual energy levels without the necessity of referring to auxiliary tables. This is done by proportioning the rises between each subshell to correspond to the Pauling energy diagram. Thus, although the subshells having the same principal quantum number will be on the same contour lamina, they will not be on the same planar level. The recognition of these contour laminae is facilitated by the use of a different color for each one. A table of this type will then be more physically correct than the previous laminar models, and it is a question as to which form has the most practical utility.

"We believe that the laminar periodic tables, in either the original or a modified form, will greatly facilitate systematic teaching of the properties of the chemical elements. Students indoctrinated with the new system cannot fail to obtain a clearer and more lasting conception of the fundamental principles of inorganic chemistry."

Note the 4f and 5f series have been split into dyads of seven apiece. This is consistent with Shchukarev (1974, p. 118) who wrote that the filling sequence among the 4f metals is periodic, with two periods. Thus, after the occurrence of a half-full 4f subshell at europium and gadolinium, the filling sequence repeats with the occurrence of a full subshell at ytterbium and lutetium (Rokhlin 2003, pp. 4–5). A similar, but weaker, periodicity (Wiberg 2001, pp. 1643–1645) is seen in the actinoids, with a half-full 5f subshell at americium and curium, and a full subshell at nobelium and lawrencium.

Note that Zn, Cd, Lu and Hg have no electron numbers above them since the underlying shells were filled at Cu, Cd, Yb, and Au respectively.

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Hsueh & Chiang's Periodic Properties of the Elements

Hsueh & Chiang, Periodic Properties of the Elements, J. Chinese Chem. Soc., 5, 5, 253-275. See the PDF.

René Vernon writes:

"A mathematical expression of the periodic law was put forward in 1937 in an article by Chin-Fang Hsueh and Ming-Chien Chiang: J Chinese Chem Soc, 5, 263 (In English.) They derived a property equation from which the numerical magnitude of a property P is related to the atomic number Z of the element in question in terms of valence V, a function of the periodic factor y, the principal quantum number n, and two parameters a and p, which are constants for a given family of elements but different for different families."

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Kurushkin's 32-Column Periodic Table & Left-step Periodic Table United

Dr Mikhail V. Kurushkin, 32-column Periodic Table & Left-step Periodic Table United:

The pursuit of optimal representation of the Periodic Table has been a central topic of interest for chemists, physicists, philosophers and historians of science for decades (Leigh, 2009; Scerri, 2009). Should the Periodic Table of Chemical Elements first and foremost serve the needs of chemists as implied by its name? Or should it start from considerations of before quantum mechanics and thus be more appealing to physicists (Scerri, 2010, 2012b)? Is there a representation which overcomes this problem? The Periodic Table is from a fundamental point of view a graphic representation of periodicity as a phenomenon of nature. While the 32-column Periodic Table, popularized by Glenn T. Seaborg, is considered by chemists the most scientifically correct representation (Scerri, 2012a), physicists apparently prefer the Left-step Periodic Table above all (Scerri, 2005; Stewart, 2010). Alternatively, it is suggested that a rigorously fundamental representation of periodicity could only take the form of a spiral as, evidently, the abrupt periods of 2-D Periodic Tables contradict the gradual increase of atomic number, and the spiral representation reconciles this debate (Imyanitov, 2016). An optimal representation is eagerly sought after both for the needs of philosophy of chemistry and chemical education as their never-ending dialogue secures a thorough methodology of chemistry. The aim of the present work is to show that the 32-column Periodic Table and the Left-step Periodic Table can co-exist in mutual tolerance in a form of what Philip Stewart has already called Kurushkin’s Periodic Table (Kurushkin, 2017), Figure 1 below.

René Vernon writes:

"Kurushkin reminds us that the Janet left step table (with Sc-Y-Lu-Lr, and He over Be), and the version of the table with the s-elements on the right (also with Sc-Y-Lu-Lr, and He over Be) are interchangeable.

"For an earlier paywall version which includes a short video see:

Kurushkin M 2018, Building the periodic table based on the atomic structure, Journal of Chemical Education, vol. 94, no. 7, pp. 976–979,

"Kurushkin’s interchangeable approach extends to tables with group 3 as either Sc-Y-La-Ac or Sc-Y-Lu-Lr. See Vernon's Yin Yang of The Periodic Table"

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Cherkesov: Two Periodic Tables

von Bichowsky FR, The place of manganese in the periodic system, J. Am. Chem. Soc. 1918, 40, 7, 1040–1046 Publication Date: July 1, 1918 

René Vernon writes:

"In this curious article, von Bichowsky, a physical chemist (1889-1951), mounted an argument for regarding Mn as belonging to group 8 (see table 1 below) rather than group 7 (table 2). His article has effectively been assigned to the dustbin of history, having apparently gathered zero citations over the past 103 years.

"Items of note in his 24-column table:

von Bichowsky made his argument for Mn in group 8, on the following grounds:

I can further add:

Moving forward precisely 100 years, Rayner-Canham (2018) made the following observations:

I've also attached a modern interpretation of von Bichowsky’s table. It's curious how there are eight metals (Fe aside) capable of, or thought to be capable of, achieving +8. I am not sure that a table of this kind with Lu in group 3 is possible, without upsetting its symmetry."

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Deming's 1923 Periodic Table, Updated by Vernon

René Vernon writes:

"Here is the 21st century version of Deming's 1923 formulation. Lacking elegance perhaps, but that’s messy chemistry for you. 25 columns wide rather than 18 or 32. Split s, p and d blocks. The connecting lines are based on four sources:

    1. Deming
    2. The literature since his time, as shown
    3. The expected behaviour of the super-heavy elements
    4. The smoothness of Z vs physiochemical property trendlines going down groups, for up to 40 physiochemical properties

"I used [the term] frontier metals to refer to the post-transition metals, since the latter term has never applied well to Al. The frontier adjective comes from a line by Russell and Lee in which they refer to Bi and Po occupying frontier territory on the PT, adjacent to the nonmetals (2006, p. 419).

"As far as metalloids are concerned, Dingle nicely summarized their status: "With ‘no-doubt' metals on the far left of the table, and no-doubt non-metals on the far right…the gap between the two extremes is bridged first by the poor (post-transition) metals, and then by the metalloids— which, perhaps by the same token, might collectively be renamed the 'poor non-metals'." (2017, p. 101)

Ref: Dingle 2017, The Elements: An Encyclopedic Tour of the Periodic Table, Quad Books, Brighton Russell AM & Lee KL 2005, Structure-Property Relations in Nonferrous Metals, John Wiley & Sons, Hoboken, NJ

Click to enlarge

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Cherkesov: Two Periodic Tables

Cherkesov AI 1984, Ionization energy of 1-6 p-electrons and formation enthalpies of lutetium and lawrencium halides. Position of these elements in Periodic system, Radiokhimiya, vol. 26, no. 1, p. 53?60 (in Russian),

René Vernon writes:

"Two Russian offerings, the first is Mendeleev style, including He over Be and the integration of the Ln and An into the main body of the table.

"The second is the first time I have seen a genuine right step table, albeit at the expense of the numbers going backwards, and the non-intuitive group numbering scheme. Bonus marks for out-of-the box thinking."

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Tutti Frutti Periodic Table

René Vernon who writes:

"As a potentially powerful teaching and learning instrument: a Tutti Frutti periodic table. I feel younger folk [will] be delighted by it. The overlay of electron configurations and blocks was designed by a colleague of mine."

Click to enlarge:

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Deming's Periodic Table With Commentry by Vernon

René Vernon writes:

Deming's 1923 periodic table is credited with popularizing the 18-column form.

I now see Deming used different thickness sloping lines to represent the different degrees of similarity between the main groups and their corresponding transition metal groups.

When I plot up to 20 chemical properties v Z going down these options I get the following values for the average smoothness of the trendlines:

I would have thought the smoothness for the line between Li-Na and Cu would be < 70%, consistent with Deming’s dashed line. But the thickness of the line would depend on what Deming took into account when he drew it. The common wisdom about groups 1 and 11 is that their similarities are: "confined almost entirely to the stoichiometries (as distinct from the chemical properties) of the compounds in the +1 oxidation state." (Greenwood & Earnshaw 2002, p. 1177). Kneen et al. (1972, p. 521) say that, "the differences between the properties of the group IA and IB elements are those between a strongly and weakly electropositive metal." On this basis I follow Deming’s dashed line. I’ve appended some notes about Group 1 and Group 11.

I have [calculated] a smoothness for C-Si-Ti-Zr-Hf of 86% versus 70% for C-Si-Ge-Sn-Pb. Since Ti shows some transition metal chemistry but not C-Si, it is perhaps plausible to keep C-Si-Ge-Sn-Pb together (as Deming did ).

Deming was a smart author. Nigh on a century later and the metrics check out.

More about group 1 and group 11

There may be a little more to the relationship between Li-Na & Cu-Ag-Au, than is ordinarily appreciated. For example:


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Ephraim's Periodic Classification

Ephraim F 1954, Inorganic Chemistry, 6th ed., Oliver and Boyd, London (revised by PCL Thorne and ER Roberts)

René Vernon writes that items of interest include:

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