Atoms, molecules and solids: research preceding World War II Returning in time to 1920, Slater had gone to Harvard to work for a Ph.D. with
Percy Bridgman, who studied the behaviour of substances under very high pressures. Slater measured the compressibility of common salt and ten other alkali halides—compounds of lithium, sodium, potassium and rubidium, with fluorine, chlorine and bromine. He described the results as "exactly in accord with Bohr's recent views of the relation between electron structure and the periodic table". This brought Slater's observation concerning the mechanical properties of ionic crystals into line with the theory that Bohr had based on the spectroscopy of gaseous elements. He wrote the alkali halide paper in 1923, having "by the summer of 1922" been "thoroughly indoctrinated ... with quantum theory", in part by the courses of
Edwin Kemble following a fascination with Bohr's work during his undergraduate days. In 1924, Slater went to Europe on a Harvard Sheldon Fellowship. After a brief stay at the
University of Cambridge, he went on to the
University of Copenhagen, where "he explained to
Bohr and
Kramers his idea (that was) a sort of forerunner of the
duality principle, (hence) the celebrated paper" on the work that others dubbed the
Bohr-Kramers-Slater (BKS) theory. "Slater suddenly became an internationally known name.". the
Bohr-Kramers-Slater (BKS) theory, • 1925:
widths of spectral lines; ideas that came very close to the
electron spins principle, • 1926 and 1927: explicit attention to
electron spin, and to the
Schrödinger equation; • 1928: the
Hartree self-consistent field, the
Rydberg formula, • 1929: the
determinantal expression for an antisymmetric wave function, • 1930:
Slater type orbitals (STOs) and atomic shielding constants, • 1931:
linear combination of atomic orbitals,
van der Waals forces (with
Jack Kirkwood, as a Chemistry Research Associate). • 1932 to 1935:
atomic orbitals,
metallic conduction, application of the
Thomas–Fermi method to metals, • 1936:
ferromagnetism, (with Erik Rudberg, later chairman of the
Nobel Prize committee for Physics)
inelastic scattering, and (with his Ph.D. student
William Shockley and close to his own Ph.D. topic), optical properties of alkali halides • 1937 and 1938:
augmented plane waves,
superconductivity,
ferromagnetism,
electrodynamics, • 1939 he published "only" a book: the definitive
Introduction to Chemical Physics, • 1940 the
Grüneisen constant, and the
Curie point, • 1941
phase transition analogous to
ferromagnetism in
potassium dihydrogen phosphate. In his memoir,
linear accelerators,
cryogenics, and, with
Francis Bitter and several other colleagues,
superconductors, These publications credit the many other scientists, mathematicians and engineers who participated. Among these, George H. Vineyard received his Ph.D. with Slater in 1943 for a study of space charge in the cavity magnetron. Later, he became director of the Brookhaven National Laboratory and President of the American Physical Society. The work of the Radiation Laboratory paralleled research at the
Telecommunications Research Establishment in England and the groups maintained a productive liaison.
George F. Koster soon completed his Ph.D., joined the faculty, and became the senior member of the group. He wrote "During the fifteen-year life of the group some sixty persons were members and thirty-four took doctoral degrees with theses connected with its work. In my report I have been unable to separate the work of Slater from that of the group as a whole. He was part of every aspect of the group's research efforts." Nesbet continued, "Every morning in SSMTG began with a coffee session, chaired by Professor Slater, with the junior members seated around a long table ... Every member of the group was expected to contribute a summary of his own work and ideas to the Quarterly Progress Report". To begin the work of the group, Slater "distilled his experience with the
Hartree self-consistent field method" into (1) a simplification that became known as the Xα method, and (2) a relationship between a feature of this method and a magnetic property of the system. These required computations that were excessive for "pencil and paper" work. Slater was quick to avail the SSMTG of the electronic computers that were being developed. An early paper on augmented plane waves used an IBM card programmed calculator. The
Whirlwind was used heavily, then the IBM 704 in the
MIT Computation Center and then the IBM 709 in the Cooperative Computing Laboratory (see below). Solid state work progressed more rapidly at first in the SSMTG, with contributions over the first few years by George F. Koster, John Wood, Arthur Freeman and Leonard Mattheis. Molecular and atomic calculations also flourished in the hands of
Fernando J. Corbató, Lee Allen and Alvin Meckler. This initial work followed lines largely set by Slater. Michael Barnett came in 1958. He and John Wood were given faculty appointments. Robert Nesbet, Brian Sutcliffe, Malcolm Harrison and Levente Szasz brought in a variety of further approaches to molecular and atomic problems. Jens Dahl, Alfred Switendick, Jules Moskowitz,
Donald Merrifield and
Russell Pitzer did further work on molecules, and Fred Quelle on solids. Slater rarely included his name on the papers of SSMTG members who worked with him. Major pieces of work which he did coauthor dealt with applications of (1) group theory in band structure calculations and (2) equivalent features of
linear combination of atomic orbital (LCAO),
tight binding and
Bloch electron approximations, to interpolate results for the energy levels of solids, obtained by more accurate methods,
People A partial list of members of the SSMTG (Ph.D. students, post-doctoral members, research staff and faculty, in some cases successively, labeled †, ‡, ৳, ¶), together with references that report their SSMTG and later activities, follows. •
Leland C. Allen †‡,
ab initio molecular calculations,
electronegativity, Professor of Chemistry Emeritus, Princeton University (2011). •
Michael P Barnett ৳¶, molecular integrals, software,
phototypesetting, cognition, • Earl Callen † •
Fernando J. Corbató †, began the molecular calculations in the SSMTG; later a pioneer of
time-sharing and recipient of the
Turing Award. •
George Coulouris ৳, worked with MPB, later professor of computer science at
Queen Mary College of the University of London. •
Imre Csizmadia ‡, molecular calculations (LiH), later Professor of Chemistry, U. Toronto,
ab initio calculations, drug design. • Jens Dahl ‡, molecular calculations, later professor of chemistry, Technical University of Denmark, wrote quantum chemistry text. • Donald E. Ellis ৳†, molecular calculations, later Professor of Physics and Astronomy at Northwestern University, "real" materials. • Arthur Freeman †‡, orthogonalized plane wave calculations, later professor of physics and astronomy at Northwestern University • Robert P. Futrelle ৳, programming methods, • Leon Gunther †‡ lattice vibrations in alkali halides, later Professor of Physics at Tufts University, focus on condensed matter theory in many areas, including superconductivity and seminal papers on nanoscopic physics & quantum tunneling of magnetization. • Malcolm Harrison ‡, (died 2007) co-developer of
POLYATOM, later professor of computer science, New York University. • Frank Herman, band structure calculations, went into RCA then IBM Research Laboratories, wrote and edited major surveys. • David Howarth ‡, solid state, later professor of computer science,
Imperial College, University of London. •
John Iliffe ৳, computer scientist. • San-Ichiro Ishigura ‡, later Professor, Ochinamizu University • Arnold Karo ‡, electronic structure of small molecules, later at Lawrence Livermore Laboratory. • C.W. Kern ‡, molecular calculations, later Professor of Chemistry, Ohio State U., published extensively. • Ryoichi Kikuchi ‡ • Walter H. Kleiner, solid state physics, continued at Lincoln Laboratory. • George F. Koster †¶, became Chairman of the Physics Graduate Committee at MIT and wrote two books on solid state physics. • Leonard F. Mattheiss †, augmented plane wave calculations, later at Bell Labs, published about 100 papers. •
Roy McWeeny ‡, valence theory, later held chairs at several British Universities and, since 1982, at the
University of Pisa, Italy. • Alvin Meckler, first major molecular calculation on Whirlwind (oxygen), later National Security Agency, •
Donald Merrifield †, molecular calculations (methane), later President of Loyola University, Los Angeles. • Jules Moskowitz ‡, molecular calculations (benzene), later chairman, Department of Chemistry, NYU, published 100 papers. • Robert K. Nesbet ‡, molecular calculations, later at IBM Almaden Research Laboratories, published over 200 papers. • Robert H. Parmenter, later professor of physics, U. Arizona, crystal properties and superconductivity. •
Russell M. Pitzer ‡, molecular calculations (ethane), later Chairman of Chemistry Department, Ohio State U, over 100 papers. • George W. Pratt Jr. †‡later Professor of Electrical Engineering and CMSE, MIT, solid state electronics. • F.W. Quelle Jr. augmented plane waves, later laser optics. • Melvin M. Saffren † •
Robert Schrieffer wrote Bachelor's thesis on multiplets in heavy atoms, later shared Nobel Prize for
BCS theory of superconductivity. • Edward Schultz • Harold Schweinler • Hermann Statz ‡, ferromagnetism, later director of research at Raytheon and recipient of 2004 IEEE Microwave Pioneer Award, • Levente Szasz, atomic structure, became professor of physics at Fordham University, published two books, • Brian T. Sutcliffe ‡, co-developer of
POLYATOM, later professor of chemistry, University of York. • Richard E. Watson ‡៛, electronic properties of metal atoms, later at Brookhaven, published over 200 papers. • E.B. White † • John Wood †¶, augmented plane waves using Hartree–Fock methods, at Los Alamos National Laboratory (died 1986), published extensively. Distinguished visitors included
Frank Boys,
Alex Dalgarno,
Ugo Fano, Anders Fröman,
Inga Fischer-Hjalmars,
Douglas Hartree,
Werner Heisenberg,
Per-Olov Löwdin,
Chaim Pekeris,
Ivar Waller and
Peter Wohlfarth.
Slater's further activities at MIT during this time In the 1962 President's Report, Jay Stratton wrote (on p. 17) "A faculty committee under the chairmanship of Professor John C. Slater has taken primary responsibility for planning the facilities in the new Center for Materials. These include a new Cooperative Computing Laboratory completed this year and equipped with an I.B.M. 709 Computer". The center was set up, in accordance with Slater's plans. It "supported research and teaching in Metallurgy and Materials Science, Electrical Engineering, Physics, Chemistry and Chemical Engineering", But in the same year, the CMSE staff included 55 professors and 179 graduate students. directed by Slater, Koster, Wood and Barnett, (2) the computer-aided design team of
Ross,
Coons and Mann, (3) members of the Laboratory for Nuclear Science, (4)
Charney and Phillips in theoretical meteorology, and (5) Simpson and Madden in geophysics (from 1964 President's report, p. 336-337). == Personal life and death ==