Periodic Table |
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| What is the Periodic Table Showing? | Periodicity |
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. The database holds information on periodic tables, the discovery of the elements, the elucidation of atomic weights and the discovery of atomic structure (and much, much more).
| Year: 1930 | PT id = 1264, Type = formulation |
Gardner's Table of Electronic Configurations of the Elements
A table of electronic configurations of the elements. Nature 125, 146 (1930). https://doi.org/10.1038/125146a0
Abstract:
"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:
- those with all "groups" complete
- those with one incomplete group
- those with two incomplete groups (transition elements)
- 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.
Note:
- there are nine groups of d-block elements [as we would now call them], and but 13 f-block elements
- La and Lu are treated as d-block elements
- while Yb is counted as an f-block element it was later realised (1937) that the 4f shell is full at Yb, hence it is not clear where Gardner would have placed it (Yb)—seemingly in the 0 column

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| What is the Periodic Table Showing? | Periodicity |
© Mark R. Leach Ph.D. 1999 –
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