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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.

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Year:  1995 PT id = 1130

Klein's Periodic Table of The Elements

Klein DJ, Similarity and Dissimilarity in Posets, Journal of Mathematical Chemistry, 18(2), 321–348 (342) (1995)

The relevance of partially ordered sets (or posets) in a wide diversity of contexts in chemistry is emphasized, and the utility of distance functions (or metrics) on such posets is noted. First a notion of "scale similarity" is introduced to make comparisons within certain so-called "scaled" posets, for which there is formulated natural "comparators", which in turn lead to associated distance functions. Beyond taking note of several chemically relevant examples of these "scaled" posets and their consequent associated similarity measures, a second chemically relevant class of so-called "shifted" posets is similarly developed, with examples. Even further extension of some aspects of the current approach is indicated, and finally the multi-posetic character of chemical periodic law is suggested.

Thanks to René for the tip!

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What is the Periodic Table Showing? Periodicity

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