Elucidation of Atomic Structure

[Mark Leach]

Hi All,

I think I have just about completed the chronological list of entries on atomic structure:

https://www.meta-synthesis.com/webbook/35_pt/pt_database.php?Button=structure

Is there anything (any topic) that is obviously missing?

Comments most welcome!

Mark

Mark Leach

meta-synthesis

[René]

Thank you Mark. This sort of chronological list is most useful.

After the heading...

Elucidation of Atomic Structure: 1800 - 1948

…the rest of it doesn’t need to be in bold; that makes it harder to read:

Dalton introduced the idea of atoms and stoichiometric combination ratios in the early nineteenth century. Atomic weights were rationilised by 1873. Radioactivity was discovered in 1896, and around this time the Group 8/18 inert/rare/full-shell gases found. The years from 1900 to 1930 saw the quantum revolution in atomic physics and atomic structure develop. The Manhattan project advanced knowledge of the heavier and radioactive elements, leading to the Seaborg periodic table and the Segrè chart. (These would have been state secrets in 1944, but by 1948 they were in the public domain). By the late 1940s, understanding atomic structure was very good:

René

--
You received this message because you are subscribed to the Google Groups "Periodic table mailing list" group.
To unsubscribe from this group and stop receiving emails from it, send an email to PT-L+uns...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/PT-L/F089F6BE-2F02-4DBD-9DCD-BF0E96FD197A%40meta-synthesis.com.

[René]

PS spelling mistake in 

rationilised

[ERIC SCERRI]

Hi Mark

What made you choose 1873 as the date when atomic weights were settled?

Eric

On Feb 20, 2026, at 5:53 PM, 'René' via Periodic table mailing list <PT...@googlegroups.com> wrote:

PS spelling mistake in 

To view this discussion visit https://groups.google.com/d/msgid/PT-L/56CEADAD-E586-4D96-AE3D-97E09A4F0A1B%40iinet.net.au.

[Mark Leach]

Hi Eric,

Good point! Very good point.

On reading your email I realised that all of the other entries were ‘first proposals’, whereas the 1873 atomic weight entry was more of a ‘finally decided’.

I have changed the atomic weight entry to Cannizzaro and 1858.

Ironic really, as the entire mini-project started with Cannizzaro!

Mark

Mark Leach

meta-synthesis