More notes on "The Disappearing Spoon"

[continuation in part]

I'm reading a book and posting comments about it. I'm on page 27:

Electron behavior drives the periodic table. But to really understand the elements, you can't ignore the part that makes up more than 99 percent of their mass---the nucleus. And whereas electrons obey the laws of the greatest scientist never to win the Nobel Prize, the nucleus obeys the dictates of probably the most unlikely Nobel laureate ever, a woman whose career was even more nomadic than Lewis's.

Maria Goeppert-Mayer. I blogged about her here. She was the poster girl for how badly science used to treat women. Kean tells a good story, but mischaracterizes one aspect which I'd like to correct and add to. At page 28, middle of the second paragraph:

After the Depression lifted, hundreds of her intellectual peers gathered for the Manhattan Project, perhaps the most vitalizing exchange of scientific ideas ever. Goeppert-Mayer received an invitation to participate, but peripherally, on a useless side project to separate uranium with flashing lights. No doubt she chafed in private, but she craved science enough to continue to work under such conditions.

I object to the characterization of "useless side project to separate uranium with flashing lights," or whatever that means. What Goeppert-Mayer was working on was the separation of uranium isotopes, under the direction of H.C. Urey at Columbia University. I suppose that work could be characterized as "useless" because ultimately gaseous diffusion solved the problem. But Goeppert-Mayer did make a valuable contribution to science during the war. The results were declassified and finally published in 1947 and became the seminal paper for the science of isotope effect chemistry.

Years ago, I corresponded with Jacob Bigeleisen, the doyen of that branch of science. He was her junior coworker at Columbia U on the Manhattan Project and was a coauthor of the 1947 paper I mentioned above. I happened to ask him about his role in isotope chemistry and he opened up, telling me a great story involving her which I already blogged on here. It's long, but well worth a read. I'm just going to re-post the part where he later told a reporter about the amazing moment when he was briefly overwhelmed by Goeppert-Mayer's brilliance. Bigeleisen had been struggling to derive an equation and to simplify it. Goeppert-Mayer glanced at his work and instantly finished it for him:

She looked at my work and asked 'why don't you finish it up by taking out the classical part?'  Without a pause, she wrote the simplified equation, saying 'Now you have it; it's all done.' I didn't immediately understand what she meant when she said to cut out the classical part. I went home. I worked on it, and eventually I got the same result. link

I suppose that those with an ax to grind could subtitle that moment in time "superior female intellect briefly overwhelms male dominance." I'm sure that she had other moments later on. But all the players are now dead and together somewhere, I suppose.

Conversations with Henry

[after a particularly tense group meeting at the start-up]

Me: Man, he about took my head off in there. I had to push back like that.

Henry: Well, don't take it too personally. He knows what he's doing. It's for the better.

Me: How so? He made me feel like crap.

Henry: When I was a grad student over at Berkeley, grown men--professors--used to curse and shout at each other over their ideas.  It was a downright mean and nasty to watch.

Me: Do you think some of that had do to G. N. Lewis?  He was still in charge then wasn't he?

Henry:  Lewis was like that, yeah. The thing is that after all that screaming and yelling over what they thought were so very important ideas--the same guys would always simmer down and go out for beers afterwards.

Bondage Is A Two-Way Street

The simple "one-way" notion of chemical bonding described back here is part of the "lone pair theory" developed by G.N. Lewis and N.V. Sidgwick. According to that theory, a neutral molecule such as ammonia donates electrons from its lone pair to a metallic Lewis acid.  But things like ethylene, not having any lone pairs, confounded the theory, since they too formed neutral metal complexes very similar to ammonia-metal complexes.

In 1935, Linus Pauling introduced the novel concept of backbonding to explain the shorter than expected Ni-C bonds observed in the electron diffraction structure of Ni(CO)₄.  Like many concepts in chemistry, backbonding is better illustrated than described:

In this simplified scheme above, CO gives electronic juice to the metal's empty and receptive d-orbital (left-hand side). At the same time, the metal gives back electrons to the CO (right-hand side) using a different full d-orbital: the two sketches overlap. They are synergistic.

Cut the vitriol, are those D's for real or not?

Here's the problem in a nutshell:

Elements 1 through 20 are theoretically supposed to build molecular structure using just those spherical and dumbell shaped thingies: the s- and p-orbitals. Theoretically speaking, no more than eight valence electrons should ever surround those atoms. This is the octet rule, and also explains why no more than four atoms ever surround those elements. The octet rule is supposed to apply to phosphorus, sulfur, and chlorine. And yet...

Fact: PF₅ and SF₆ exist, in apparent violation the octet rule. PF₅ has ten valence electrons (2 in each bond) and SF₆ has twelve. Also, some pretty common species like phosphate, sulfate, and perchlorate, appear to violate the octet rule. Those are pretty serious charges. Good men may have even killed themselves over the very issue. Link

Look, intelligent people disagree on many topics. As an aside, the ancient name for sulfuric acid was vitriol, which nowadays mostly means nasty rhetoric. But consider the word's origins. According to the OED, vitriol, H₂SO₄, was so-named because of the glassy-like appearance of concentrated sulfuric acid. I love how so many words are, in the end, just metaphors. Vitriol is an ancient substance, and came to us by way of alchemy. By the way, we spell it "sulfuric" and the Brits spell it "sulphuric."

Bored yet?

You should have seen what I was going to post on this topic. Something about D-orbitals.

Lewis Structures: What Is Essential Is Invisible

After physicists discovered and defined the basic properties of the naked electron, the next big question was how to describe and understand them in the context of atoms and molecules, thus encroaching the natural domain of chemistry.

G.N. Lewis invented Lewis structures as a way to describe and understand how electrons surround atoms and also how they hold molecules together.  He did this in a non-mathematical, pictorial way in the early 20th century before the birth and subsequent ascent of quantum mechanics. Lewis depicted atoms and their electrons as cubes which could be joined at their edges, vertices, and faces:

The physicists regarded Lewis's theory as laughably crude, particularly the notion that electrons were fixed at certain positions. Lewis in turn was critical of the physicists' idea that electrons were completely fluid, as for example, in J. J. Thomson's plum-pudding model of the atom, because it seemed incapable of explaining the definitive shapes of molecules, for example, the tetrahedral geometry of carbon in countless organic compounds.

By the mid 1920's Lewis had dropped his 3D cubic portrayal of electronic structure; what survives today is rather like a flat 2D projection of those cubes onto a plane.  Lewis would have drawn hydrogen cyanide (the molecule that may have killed him) as:

"What is essential is invisible to the eye"

The lasting importance of Lewis's theory is that it provided chemists with a way (albeit simplified) of visualizing the electronic structures of atoms and molecules. That is perhaps why it endures.

Gilbert Newton Lewis (1875-1946)

Poor under appreciated G. N. Lewis, perhaps the most famous chemist never to win a Nobel Prize, despite having been nominated 35 times. A few of his accomplishments included:

• From 1912 to 1941, at a time went Germany still dominated the field, he put the University of California chemistry department on the international map: Lewis did for Berkeley chemistry what Oppenheimer and Lawrence did for physics there.
• In 1923, he formulated the electron-pair theory of acid-base reactions. In the so-called Lewis theory of acids and bases, a "Lewis acid" is an electron-pair acceptor and a "Lewis base" is an electron-pair donor. It's hard to overemphasize how conceptually useful this concept remains in chemistry.
• Also in 1923, Lewis published a monograph on his theories of the chemical bond and formulated what later became known as the covalent bond. These ideas reached back to 1916. 
• Lewis coined the term "photon" and was involved in many of the theoretical and experimental problems of his day including: electrolytes, thermodynamics, and valence bond theory. 

So what went wrong? According to the Wiki:

In 1946, a graduate student found Lewis's lifeless body under a laboratory workbench at Berkeley. Lewis had been working on an experiment with liquid hydrogen cyanide, and deadly fumes from a broken line had leaked into the laboratory. The coroner ruled that the cause of death was coronary artery disease, but some believe that it may have been a suicide. Berkeley Emeritus Professor William Jolly, who reported the various views on Lewis's death in his 1987 history of UC Berkeley’s College of Chemistry, "From Retorts to Lasers", wrote that a higher-up in the department believed that Lewis had committed suicide.

Is this true? Why? I intend to read Jolly's book. Meanwhile, Patrick Coffey, a businessman and former chemist who moonlights as a historian, thinks otherwise:

He was brilliant intellectually, he could cut right through to the simplest solution to any problem. The downside of Lewis was he was very prickly and made a lot of enemies.

He'd been home-schooled as a child. He never seemed comfortable outside his closed environment. He probably needed to get in more fights on the playground.

He built his own support system, but when he got out of that system, if anybody gave him any slight at all he'd hold a lifelong grudge. Lewis's exacting nature sometimes got the best of him.

By the time of his death, he'd completely estranged himself from at least four Nobel laureates, and one of them was Irving Langmuir.

Yeesh, Coffey makes the Chemistry Nobel sound like the Oscars. He goes on to say:

There's nothing criminal here, but it's interesting, that probably the two greatest physical chemists [Lewis and Langmuir] of the 20th century had lunch together the day one of them died. 

Read the linked article and make up your own mind. I'm still gathering facts.