What are Transition Elements? Transition metals, atomic structure and the periodic table - Part 1

Professor Davis explains where the term "Transition Metal" or "Transition Element" comes from and how it is linked to the evolution of our understanding of atomic structure.
Apologies if you hit a paywall. I will look for publicly available links!!!
Langmuir's 1919 Paper:
pubs.acs.org/doi/pdf/10.1021/...
Bury's 1921 Paper:
pubs.acs.org/doi/pdf/10.1021/...

[@ronalddavis670]

Great graphics

[@mikechaves2868]

Wow, thanks Professor I really enjoyed the history review (Irving Langmuir's 4th postulate) and depth you put into this; keep it up!

[@ChemSurvival]

Thanks for the kind words, Mike! Summer teaching at Georgetown is a heavy lift, but I'm determined to get a 'Table Tuesday' squeezed in each week all summer long. *fingers crossed*

[@Stop-and-listen]

Great explanation!

[@ChemSurvival]

Thanks! Glad you enjoyed the video! Hope you'll subscribe and stay tuned for part two

[@df4250]

I'm a great fan of your Great Courses on Chemistry and the Periodic Table, but I was wondering if you could explain the "transition" of electronic orbitals from the highly structured behaviour in atoms, through the still structured behaviour of molecular orbitals, through to the apparently more "chaotic" behaviour of electrons in transition metals? Is there any understanding or theory that explains what allows the loosely held outer electrons of transition metals to essentially break free of complying with the rigours of quantisation and roam freely around the metallic lattice? Or do they comply to some kind of quantum behaviour? I'm familiar with Valence Bond Theory and Molecular Orbital Theory, but have never quite understood what constraints (if any) exist for the outer electrons of transition metal lattices.

[@ChemSurvival]

Thanks for the comment (and the interest in my Great Courses projects! - they were a decade-long labor of love for me). As for your questions regarding lack of degeneracy in d-orbitals and regarding metallic bonding: those will require some research on my part. My PhD is in biophysical (protein) chemistry and I currently teach organic. d-orbitals are a rare site in both disciplines!

[@df4250]

@@ChemSurvival Fair enough, Prof Davis. You certainly did very well to cover topics not entirely within your field (from the Transition Metals through the "Post Fermium wars" all the way up to Element 118 (Og) 🙂. If you know of any reference that may closely approach the topic I'd raised, I'd be interested in looking it up. Thanks for your reply.