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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.

Use the drop menus below to search & select from the more than 1100 Period Tables in the database:

Text search:       

The 10 Periodic Tables most recently added to the database:

2012   Itch: A Book & TV Drama About a Boy Who Collects The Chemical Elements
2020   Workshop on Teaching 3d-4s Orbitals Presented by Dr. Eric Scerri
2020   Vernon's Periodic Treehouse
1959   Mendoza's Neuvo Sistema Periodico
1994   Treplow's Periodic Table of The Atoms
2020   Lehikoinen's Circular Clock Form
2020   Molar Magnetic Susceptibilities, Periodic Table of
1926   Friend's Periodic Table (1926)
1917   Friend's Periodic Table (1917)
2020   Spiral Electron Spin Periodic Table


Itch: A Book & TV Drama About a Boy Who Collects The Chemical Elements

Meet Itch – an accidental, accident-prone hero. Science is his weapon. Elements are his gadgets.

All-action adventure perfect for fans of Alex Rider and Young Bond.

Itchingham Lofte – known as Itch – is fourteen, and loves science, especially chemistry. He's also an element-hunter: he's collecting all the elements in the periodic table. Which has some interesting and rather destructive results in his bedroom.

Then, Itch makes a discovery. A new element, never seen before. At first no one believes him – but soon someone hears about the strange new rock and wants it for himself. And Itch and his family are catapulted into a breathless adventure with terrifyingly high stakes...

The debut novel from BBC radio presenter Simon Mayo.

Children's book Itch by Simon Mayo is available from Amazon and all good bookshops, ISBN: 9780552565509. The book has been made into a TV Series, filmed in Western Australia, and is available on the BBC iPlayer.

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Workshop on Teaching 3d-4s Orbitals Presented by Dr. Eric Scerri

Dr. Eric Scerri, UCLA Department of Chemistry & Biochemistry, discusses many of the issues concerning the periodic table: the aufbau principle, Madelung's rule, the electronic and anomalous electronic structures of the transition elements, the Sc2+ ion, the Janet Left Step, Group 3: Sc, Y, Lu, Lr vs. Sc, Y, La, Ac, atomic spectroscopy, etc.

Many of the topics that concern those of us interested in the periodic table are discussed.

Thanks to Eric Scerri – who appears – for the tip! 
See the website and Eric's Twitter Feed.

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Vernon's Periodic Treehouse

René Vernon's Periodic Treehouse of the Elements, fearuring the World's longest dividing line between metals and nonmetals.

René writes:

I can't remember what started me off on this one. It may have been Mendeleev's line, as shown on the cover of Bent's 2006 book, New ideas in chemistry from fresh energy for the periodic law.

There are a few things that look somewhat arbitrary, so I may revisit these:

Click to enlarge:

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Mendoza's Neuvo Sistema Periodico

A memorial work, Ley De Configuraciones Electronicas, published posthumously in 1965 to honor Oswaldo Baca Mendoza (1908–1962 Cusco, Peru) and his 1959 Neuvo Sistema Periodico. Download the full PDF file (in Spanish).

Click to enlarge:

Thanks to Julio Gutierrez Samanez for the infomaton, etc.

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Treplow's Periodic Table of The Atoms

R.S. Treplow, J. Chem. Educ. 1994, 71, 12, 1007: The Periodic Table of Atoms: Arranging the Elements by a Different Set of Rules.

"Although periodic tables differ greatly in their appearance, examination shows they are all designed according to a common set of conventions. This paper reviews those conventions and asks how the table would look under a different set of rules."

Ground-state multiplicity vs. atomic number for elements 1 to 103. Subblocks are labeled S, P, D & F. Lines connecting the dots show the "ideal" pattern. Atoms not on the lines are "nonideal" (where ideal refers to Madelung's rule):

Thanks to René Vernon for his help.

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Lehikoinen's Circular Clock Form

Otto Lehikoinen writes:

"A circular form separating 1s orbital to the center, set it on a wall clock as there are 48 elements of main periods, thus can be used as markers for half hours. Group 4 is centered on noon and group 7 starts the afternoon, to get anions and cations with the same but opposite charge to be beside each other. Thus the noble gases are centered on midnight which is easily remembered by neon (and other noble gas) lights. The minute hand hits the 40 d-block elements giving an accuracy of 1.5 minutes and seconds could be read from lanthanides and actinides."

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Molar Magnetic Susceptibilities, Periodic Table of

Periodic Table of Molar Magnetic Susceptibilities by René Vernon, who writes:

I had read that the lanthanides were characterised by their magnetic properties, but never fully appreciated what this means. To this end, here is a table of Molar Magnetic Susceptibility (MMS) values (χ) for the elements, where MMS is a measure of how much a material will become magnetised in an applied magnetic field.

Formally, MMS is the ratio of magnetisation M (magnetic moment per unit volume) to the applied magnetising field of intensity H, allowing a simple classification into two categories of most materials responses to an applied magnetic field:

Alignment with the magnetic field, χ > 0, gives rise to paramagnetism
Alignment against the magnetic field, &chi; < 0, gives rise to diamagnetism

Six observations:

1. The average value for each block is:

2. Lanthanides having unpaired 4f metals (Ce to Tm) have magnetic susceptibilities two to four orders of magnitude larger than those of "normal" metals.

3. Mn (511), Pd (540), O (3415) [this is actually the triplet diradical molecule O2] & Bi (-280) stand out. [A magnetic cross would be good for repelling a bismuth vampire.]

4. MMS reduces going down all groups of the d-block. The average reduction going from 4d to 5d is 50%.

5. In group 3 there is a reduction of 48% on going from Y to La. If Lu is instead placed under Y the reduction is 2%.

6. There are at least six, rather than three, ferromagnetic metals.

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Friend's Periodic Table (1926)

Vallance RH & Eldridge AA, A Text-Book of Inorganic Chemistry, Vol. VII, Part III, Chromium and its Congeners, JN Friend (ed.) Charles Griffin & Company, London (1926), front paper.

René Vernon (who found this formulation) writes:

"I can't recall seeing a table in which the lanthanoids were allocated in quite such a manner: across seven groups. And, 16 such lanthanoids shown. Even curiouser, Argon = A; xenon = X; are shown in group 0. Wonderful nomenclature from nearly a century ago."

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Friend's Periodic Table (1917)

H. F. V. Little, A Text-Book of Inorganic Chemistry, Vol. IV, Aluminium and its Congeners, including the Rare Earth MetalS (Group III. of the Periodic Table), JN Friend (ed.) Charles Griffin & Company, London (1917), front paper.

Thanks to René Vernon for the tip.

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Spiral Electron Spin Periodic Table

The Spiral Electron Spin Periodic Table, By Justine Colburn, who also developed the Genesis formulation.

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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