August 2012 Archives

Thu Aug 30 23:04:17 PDT 2012

Bill Shockley and His Thesis

Bill Shockley won the Nobel prize, with John Bardeen and Walter Brattain, for the invention of the transistor in 1956. I had always thought that Bardeen was the theoretician, Brattain the experimentalist, and that Shockley was the hard driving technical manager of the trio.

I am not sure how I came by that simple view, but it is wrong. Shockley did his Ph.D. work studying the electronic structure of solids, and Sodium Chloride or NaCl, in particular. He did early Hartree Fock calculations to solve the Schrodinger equation for this material (in fact J. C. Slater, of 'Slater determinant' fame, was his supervisor at MIT).

If you want to examine the details of Shockley's quantum mechanical calculations for solids for yourself, here is Bill Shockley's thesis. This was written in 1932, just 15 years before the invention of the transistor in 1947. I cannot help but suspect that Bardeen and Shockley's quantum mechanical knowledge inspired them to examine the details and practical applications of semiconductor materials...and their discoveries changed the world.

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Fri Aug 24 12:54:35 PDT 2012

Potential Energy Functions for Atomistic Simulation

Here is an interesting paper (or summary of an old Nato workshop course). It is by Shneior Lifson who sadly died in 2002. It was produced in 1981 and summarizes the details of potential energy functions, or forcefields, for the atomistic simulation of organic materials. Recommended reading for practitioners of the methods established by Lifson and his colleagues.

Potential Energy Functions for Structural Moleular Biology by Shneior Lifson, 1981

Posted by ZFS | Permanent link