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: 2022 | PT id = 1259, Type = formulation |
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:
- Deming
- The literature since his time, as shown
- The expected behaviour of the super-heavy elements
- 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
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| What is the Periodic Table Showing? | Periodicity |
© Mark R. Leach Ph.D. 1999 –
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