Sir John Anthony Pople, FRS, (October 31, 1925 – March 15, 2004) was a theoretical chemist. Born in Burnham on Sea, Somerset, England, he attended Bristol Grammar School. He won a scholarship to Trinity College, Cambridge in 1943. He received his B. A. in 1946. Between 1945 and 1947 he work at the Bristol Aeroplane Company. He then returned to Cambridge University and was awarded his doctorate degree in mathematics in 1951. He moved to the United States of America in 1964, where he lived the rest of his life, though he retained British citizenship. Pople considered himself more of a mathematician than a chemist, but theoretical chemists consider him one of the most important of their number.
Major scientific contributions
His scientific contributions are in four different areas:
Statistical mechanics of water
His early paper on the statistical mechanics of water, according to Michael J. Frisch, "remained the standard for many years. This was his thesis topic for his Ph D at Cambridge supervised by John Lennard-Jones.
Nuclear magnetic resonance
In the early days of nuclear magnetic resonance he studied the underlying theory and coauthored a text book. 
He made major contributions to the theory of approximate molecular orbital (MO) calculations, starting with one identical to the one developed by Rudolph Pariser and Robert G. Parr on pi electron systems, and now called the Pariser-Parr-Pople method. Subsequently, he developed the methods of Complete Neglect of Differential Overlap (CNDO) (in 1965) and Intermediate Neglect of Differential Overlap (INDO) for approximate MO calculations on three-dimensional molecules, and other developments in computational chemistry. He coauthored a book on these methods with David Beveridge.
Ab Initio Electronic Structure Theory
He pioneered the development of more sophisticated computational methods, called ab initio quantum chemistry methods, that use basis sets of either Slater type orbitals or Gaussian orbitals to model the wave function. While in the early days these calculations were extremely expensive to perform, the advent of high speed microprocessors has made them much more feasible today. He was instrumental in the development of one of the most widely used computational chemistry packages, the "GAUSSIAN"(tm) suite of programs, including coauthorship of the first version, Gaussian 70. One of his most important original contributions is the concept of a model chemistry whereby a method is rigorous evaluated across a range of molecules.  He instigated the quantum chemistry composite methods such as Gaussian-1 (G1) and Gaussian-2 (G2). He was a founder of the Q-Chem computational chemistry program.
Career and honours
After obtaining his Ph D, he was a research fellow at Trinity College, Cambridge and then from 1954 a lecturer in the mathematics faculty at Cambridge. In 1958, he moved to the National Physical Laboratory, near London as head of the new basics physics division. In 1964 he moved to Carnegie Mellon University in Pittsburgh, Pennsylvania, where he had experienced a sabbatical in 1961 to 1962. In 1993 he moved to Northwestern University in Evanston, Illinois where he was Board of Trustees Professor of Chemistry until his death.
He received the Nobel Prize in Chemistry in 1998. He was made a fellow of the Royal Society in 1961. He was made a Knight Commander (KBE) of the Order of the British Empire in 2003. He was a founding member of the International Academy of Quantum Molecular Science.
* An IT room and a scholarship are named after him at Bristol Grammar School.
* He was once denied membership in the American Chemical Society, as he held no degrees in chemistry.
- ^ a b Obituary by The Guardian
- ^ a b c d Reflections on John Pople's Career and Legacy, Michael J. Frisch, 17 March 2004
- ^ Pople, J. A. (1951). "Molecular Association in Liquids: II. A Theory of the Structure of Water". Proceedings of the Royal Society, A 205: 163.
- ^ Pople, J. A.; W. G. Schneider, and H. J. Bernstein (1959). High Resolution Nuclear Magnetic Resonance. New York: McGraw-Hill.
- ^ Pariser-Parr-Pople
- ^ Pople, J. A.; D. Beveridge (1970). Approximate Molecular Orbital Theory. McGraw-Hill.
- ^ Gaussian's page on John Pople
- ^ Pople, J. A. (1973). "Theoretical Models for Chemistry". Proceedings of the Summer Research Conference on Theoretical Chemistry, Energy Structure and Reactivity , Ed. D. W. Smith. New York: John Wiley & Sons.
- ^ Pople's Q-Chem page
- ^ John Pople Chronology at Gaussian.
- ^ Official homepage of the Nobel Prize in Chemistry in 1998
List of chemists