March 22, 1954

Professor Linus Pauling

Department of Chemistry

California Institute of Technology

Pasadena 4, California

Dear Dr. Pauling:

Thank you for your letter. I am sorry that I cannot come to your meeting, but I hope that it will be an interesting and successful one.

I am now inclined to agree that you are probably right about the danger of the sigma phase paper being turned down because of its length. Therefore, I guess, trimming is in order, even if it means the deletion of worth-while material. I have long enough or too long stood in the way of getting the paper into press by sitting on it here, and so I don't want to see it delayed any longer; I will therefore go along with whatever changes you and Gunnar want to make, and I suggest that Gunnar save time by not bothering to clear details with me. My greatest fear is that if the paper is delayed much longer its contents will be old hat.

I am confident that whatever Gunnar sends off for publication will be a good paper, and I will be happy when it is at last in print.

Things here are going very slowly at the moment. For a year or so I chased a will o' the wisp on an attempt to find another Na4Pb phase that would explain Stillwell and Robinson's old powder data. We are now getting started on some Na-Pb phases between NaPb and Na₄Pb with the expectation of getting somewhere. I have been badly stuck on the delta phase (MoNi) for a number of months. It is tetragonal, with probable space group (as indicated by extinctions) P 4₂2₁2 with a₀ = 9.12 A., c₀ = 8.90 A., 54 atoms in the cell. The interesting thing is that the Okl reciprocal lattice net looks essentially identical to the hkO net in the sigma phase! However, with the lower symmetry (no center of symmetry) and large number of atoms it is no cinch to devise a structure which looks like the sigma phase in projection down both a and b axes. However, we are trying some new things and hope to have the structure before too long. We have some data on some of Geoffrey Wilkinson's "super sandwiches", one with molybdenum and one with tungsten. These are going slowly, as in both compounds there are two molecules in the asymmetric unit.

Sorry to learn of your bad luck on your India and round-the world trip.

Sincerely yours,

Dave

David P. Shoemaker

DPS:fd

cc: Professor Gunnar Bergman