Periodic Table
T-Shirts & more
from the
meta-synthesis



Merch Store


previous home next
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 hold information on periodic tables, the discovery of the elements and elucidation of atomic weights (and more).

Use the drop menus or search box (below) to search & select from the more than 1350 Period Tables in the database: 

  Search by Text String:       


Periodic Tables from the year 2026:

2026   The Approximate Chemical Formula of the (Observable) Universe
2026   Pairs and Squares Periodic Table


Year:  2026 PT id = 1347, Type = misc

The Approximate Chemical Formula of the (Observable) Universe

From xkcd, The Approximate Chemical Formula of the (Observable) Universe:

Thanks to Marcus for the tip!

Top of Page

Year:  2026 PT id = 1365, Type = formulation

Pairs and Squares Periodic Table

"Pairs and Squares" Periodic Table by Leonid A. Levin of Boston University

Leonid writes:

"All the tables [in the PT Database] share a common problem: their irregularity exceeds by far their periodicity.

"In my youth I was greatly bothered by this. Yet, taking advantage of a few patterns in atomic orbitals allows a complete elimination of all irregularities, putting all periods in a perfect pattern.This perfectly regular rendition would be much more comfortable, especially at one's first high school exposure to this Science symbol.I am attaching such "Pairs and Squares" rendition with a brief explanation."

"Read more in the full 'Pairs and Squares' paper, here."

Top of Page

previous home next
What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –


Queries, Suggestions, Bugs, Errors, Typos...

If you have any:

Queries
Comments
Suggestions
Suggestions for links
Bug, typo or grammatical error reports about this page,

please contact Mark R. Leach, the author, using mark@meta-synthesis.com

This free, open access web book is an ongoing project and your input is appreciated.