Eric Scerri
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If one knows how the electrons in an atom are arranged, especially in the outermost shells, one immediately understands many properties of an atom, such as how it bonds and it’s position in the periodic table. I have spent the past couple of years looking closely at the historical development of this concept as it unfolded at the start of the 20th century.
What I have found has led me to propose a new view for how science develops, a philosophy of science if you will, in the grand tradition of attempting to explain what science really is. I am well aware that such projects have fallen out of fashion since the ingenious, but ultimately flawed, attempts by the likes of Popper, Kuhn, and Lakatos in the 1960s and 70s. But I cannot resist this temptation since I think I may have found something that is paradoxically obvious and original at the same time.
The more one looks at how electronic configurations developed the more one is struck by the gradual, piecemeal and at times almost random development of ideas by various individuals, many of whose names are completely unknown today even among experts. Such a gradualist view flies in the face of the Kuhnian notion whereby science develops in a revolutionary fashion. It goes against the view, fostered in most accounts, of a few heroic characters who should be given most of the credit, like Lewis, Bohr, or Pauli.
If one looks at the work of the mathematical physicist John Nicholson, one finds the idea of the quantization of electron angular momentum that Bohr seized upon and made his own in his 1913 model of the atom and his own electronic configurations of atoms. In looking at the work of the English chemist Charles Bury, one finds the first realization that electron shells do not always fill sequentially. Starting with potassium and calcium, a new shell is initiated before a previous one is completely filled, an idea that is especially crucial for understanding the chemistry of the subsequent transition elements, starting with the element scandium.
Photo:
Niels Bohr. |
This was followed by the work of the then Cambridge University graduate student, Edmund Stoner, who was the first to use the third quantum number to explain that electron shells were not as evenly populated as Bohr had first believed. Instead of a second shell consisting of two groups of four electrons that Bohr favored, Stoner proposed two groups of two and six electrons respectively...
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Additional resources
Scerri, Eric R. | UCLA Chemistry and Biochemistry
Eric Scerri (From Wikipedia, the free encyclopedia)
Source: OUPblog (blog)