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Johann Döbereiner found triads: a sequence of three similar elements, where the middle element has a mass equal to the average of the least and most massive.
A brief biography can be found on the Nature website. -
Berzelius' electronegativity table of 1836.
The most electronegative element (oxygen or Sauerstoff) is listed at the top left and the least electronegative (potassium or Kalium) lower right. The line between hydrogen (Wasserstoff) and gold seperates the predomently electronegative elements from the electropositive elements. -
The French geologist , Alexandre-Émile Béguyer de Chancourtois was the first person to make use of atomic weights to produce a classification of periodicity. He drew the elements as a continuous spiral around a metal cylinder divided into 16 parts. -
One of the first attempts at a periodic table that arranged the known elements by atomic weight and chemical property, was by John Newlands and is known as "Newlands Octaves". -
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Mendeleev [also spelled Mendeleyev in English] recounted in his diary: "I saw in a dream a table where all the elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper." -
This is rather similar to the Mendeleev attempt at the same time. -
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Model of Crookes’ vis generatrix of 1898, built by his assistant, Gardiner. From: Proc. R. Soc. Lond. 63, 408.
The vertical scale represents the atomic weight of the elements from H = 1 to Ur = 239.
Missing elements are represented by a white circle. Similar elements appear underneath each other -
Henry Moseley (1887-1915) subjected known elements to x-rays and was able to derive a relationship between x-ray frequency and number of protons. -
This model, made by the Science Museum in 1925, provides a rare physical realisation of arguably the earliest periodic system of for the elements. -
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Zmaczynski's fan-shaped system of 1937 -
The modern periodic table is based on quantum numbers and blocks,A periodic table can be constructed by listing the elements by n and l quantum number -
Scheele's system of 1950 -
John D Clark's 1950 chart. It looks as though the experience of producing the 1949 version for Life Magazine caused him to have a radical rethink. John D. Clark, A modern periodic chart of chemical elements. -
First published in 1964, it explicitly showed the location of lanthanides and actinides. The elements form a two-dimensional spiral, starting from hydrogen, and folding their way around two peninsulars, the transition metals, and lanthanides and actinides. -
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By John T Hortenstine Jr. of the R.W. Johnson Pharmaceutical Research Institute, The Non-Scientists Concept of the Periodic Table of the Elements, for example "Zirconium, in Fake Diamonds", etc. -
This spiral, inspired by Stewart's Chemical Galaxy, is based on the modern periodic table with the elements strictly arranged in the increasing order of their atomic number and in accordance with their electron configurations. -
ekka Pyykkö at the University of Helsinki has used a highly accurate computational model to predict electronic structures and therefore the periodic table positions of elements up to proton number 172 - far beyond the limit of elements that scientists can currently synthesise.