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

[Continued from here]

At Henry's suggestion, I wrote to Jacob Bigeleisen. He replied:*

[Salutation]:

How did I get into isotope chemistry? In 1943 I worked at SAM Laboratory at Columbia U (Manhattan Project). My initial assignment was to look for isotope shifts in the electronic spectra of uranium compounds (principally uranyl ion). The purpose of this research was to examine the feasibility of a photochemical separation of the uranium isotopes for military purposes. It was a small project. It was here that I became acquainted with Maria Mayer. She worked on the theory of the spectra. I did experiments and consulted with her regularly about my results and her results. The project was reviewed in July 1943 by James B. Conant and Richard C. Tolman, two high officials in the war time science effort. They brought along as an advisor E.B. Wilson, Jr., the outstanding spectroscopist and quantum chemist from Harvard. The Committee found our work very interesting, but recommended that it be discontinued. The time schedule for any practical application of a photochemical process was inconsistent with the plans for the production of a weapon. People like Urey favored a small scale continuing effort as part of scientific intelligence. Was this a path the Germans could be following?

The dozen or so people working on the project were reassigned in September. I was assigned to write up the work of the project as a final report, which was issued under the name of H.C. Urey. Maria Mayer went to the hospital in October 1943 for gall bladder surgery. In late November an assistant of Urey's (one of his former graduate students) Isidor Kirschenbaum came to see me. He said 'you know all about spectra of uranium compounds.' I said I didn't know everything; what was known, I knew. He said: 'Here is this formula. Put in the information about all uranium compounds and give me the results. We are interested in the possible chemical separation of the uranium isotopes. What we would be particularly interested in would be a volatile compound, which dissociates in the vapor. We have reason to believe that this would be very favorable.'  I asked: 'How do you know this?'  He said he could not tell me. I looked at the formula he gave me. It was the Urey-Greiff equation. I told him that I was not familiar with that whole field and I would have to study it out before I put numbers into the equation. He then said: 'Don't you know there is a war on?' He reported to Urey that I was not a very cooperative person.

Well I studied out the Urey-Greiff equation. There are a lot of factors. For uranium compounds, I could see that we did not know some of the factors; for some of the factors the number was of the order +1.001; for some of the factors the number was -1.001. With the computing facilities available then (desktop mechanical calculators) one could get any final answer from +1.00x to -1.00x from the Urey-Greiff equation. So, I decided I would look into a different approach. In chemistry and most of physics, one does not measure absolute quantities. One measures differences. Would it be possible to calculate differences directly instead of absolute quantities and then subtract the two to get the isotope effect? I started on this approach and I completed the zero point energy and the Boltzmann excitation terms.

On Monday after Thanksgiving 1943 Maria Mayer returned to work. She asked me how I was coming along with the final report. I told her I was not working on it. 'What was I doing?' she asked. I explained the problem to her and showed her my progress. This was a general type of problem she was thoroughly familiar with. In collaboration with George E. Kimball and Walter Stockmayer, she had calculated the isotope effect in the reaction HD + H₂O = H₂ + HDO. This reaction was used to produce heavy water at a plant in Trail B.C. and in Norway.) She was also familiar with the general subject since she and her husband, Joe Mayer, had just written a book on statistical mechanics. I had studied this book as a graduate student. She found my approach very interesting, very sensible and very promising. She then volunteered by asking me whether she could join me in working on this project. I said sure, that would be great. So she did and by the end of the day we completed the derivation of the Bigeleisen-Mayer equation. [1] We then made a number of predictions of systems that would be hopeless for uranium isotope separation and pointed to potential interesting avenues. An experimental program was then organized under Clyde Hutchinson. I worked on that for about a half a year.

Urey was too occupied to look into what we had done. His deputies either did not understand or did not believe that a green Ph.D. new to the field could simplify the Urey-Greiff equation to the point where meaningful calculations could be made. There was a lot of secrecy and people were not told everything they needed to know to make the best progress. In April I became involved in determining the structure of UF₆ by spectroscopic means. I did the experiments at American Cyanamid in Stamford, Conn., where they had outstanding spectroscopic equipment. I worked on the analysis of the the spectra with Maria Mayer, who had tried two years earlier in collaboration with Edward Teller to predict the vibrational structure of UF₆ from first principles! I told Maria Mayer when I started on that project that it was an experimental project, not one for calculation. She asked me whether I could do it (determine the Raman spectrum). She took out of her drawer the infra-red spectrum which had been measured by John Turkevich at Princeton. Neither she, Turkevich nor Edward Teller were able to decipher the infra-red spectrum of UF₆. While Maria Mayer and I worked on the analysis of the spectra, from which we deduced unequivocally the regular octahedral structure, in contrast to the electron diffraction results of Simon Bauer, she told me that she had written a summary report of our work on the theory of isotope effects in equilibria and our calculations relevant to uranium isotope separation.

She prepared this report at the request of Martin Kilpatrick, Urey's deputy to whom we reported. The reason for this was that Edward Teller was to make one of his regular consulting visits from Los Alamos. Kilpatrick showed Teller Maria Mayer's report of our work. Teller had also worked on this problem (there is a 1938 paper by Herzfeld and Teller). He told Kilpatrick that the work was correct and first class. Kilpatrick reported to Maria Mayer that Teller approved of the work. Fine. That made her furious. She said to me: 'They trust Edward Teller and not me.'

Regards to Henry. Pass this message on to him.

Jacob Bigeleisen

__________________________________
* Bigeleisen wrote to me in longhand. I transcribed it here. I supplied the links as well in case anyone was interested.

[1] Bigeleisen later retold a reporter about this amazing moment when he was briefly overwhelmed by Maria Mayer's brilliance:

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.

Conversations with Henry: She Was A Piece Of Work

[continued from back here]


Henry: Jake didn't really discover kinetic isotope effects -- he just explained them first. Plus I think he had some help.


Me: From whom?

Henry: Maria Mayer. Boy she was piece of work. Smart as a whip. She was the poster girl for how badly science used to treat women.

Me: Really?


Henry: Yes. She won the Nobel Prize eventually. Not in Chemistry though, but Physics. She developed the shell structure model of atomic nuclei. She ended up down by you you know.


Me: You mean UCSD?


Henry: Yep. But she started out in Germany -- as Maria Goeppert. She was friends with all the big time physicists back then. You should look her up. Interesting story. But if you're interested in isotope effects, why don't you just write Jake -- he's a nice guy.  


Me: Thanks, I will. Can I mention you?


Henry: Please do and give him my regards.

I look at my cards and frown. I discard two and ask for two more.

[story continued here]