| Joel M. Bowman | |
| Birth Date: | Jan. 16, 1948 |
| Workplaces: | Emory University |
| Education: | University of California, Berkeley California Institute of Technology |
| Thesis1 Title: | and |
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| Thesis1 Url: | and |
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| Thesis1 Year: | and |
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| Doctoral Advisor: | Aron Kuppermann |
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Joel Mark Bowman is an American physical chemist and educator. He is the Emeritus Samuel Candler Dobbs Professor of Theoretical Chemistry at Emory University.[1]
Bowman spent his early years in Boston, Massachusetts, attending school in Dorchester and then moving to Brookline. He received a bachelor's degree from the University of Massachusetts at Amherst in 1969. He went to California Institute of Technology for graduate school, and was advised by Donald Truhlar (as he was leaving for the University of Minnesota) to choose Aaron Kuppermann as his advisor. Completing his Ph.D. in 1974, he began his career at Illinois Institute of Technology in Chicago, where he began collaborating with Al Wagner at Argonne National Laboratory. He held a faculty appointment at Argonne from 1978 to 1991. In 1982-1983 he spent a sabbatical at the James Franck Institute of the University of Chicago, and worked as a consultant at Bell Laboratories in 1984. Bowman moved to Emory University in 1986, where he has spent the rest of his career to date.[2]
Bowman's research interests are in basic theories of chemical reactivity.[1] He is well known for his contributions in simulating potential energy surfaces for polyatomic molecules and clusters. Approximately fifty potential energy surfaces for molecules and clusters have been simulated employing his permutationally invariant polynomial method.[3]
Simulating potential energy surfaces (PESs) for reactive and non-reactive systems is of broad utility in theoretical and computational chemistry. Development of global PESs, or surfaces spanning a broad range of nuclear coordinates, is particularly necessary for certain applications, including molecular dynamics and Monte Carlo simulations and quantum reactive scattering calculations.
Rather than utilizing all of the internuclear distances, theoretical chemists often analytical equations for PESs by using a set of internal coordinates. For systems containing more than four atoms, the count of internuclear distances deviates from the equation 3N−6 (which represents the degrees of freedom in a three-dimensional space for a nonlinear molecule with N atoms).[4] [5] As an example, Collins and his team developed a method employing different sets of 3N−6 internal coordinates, which they applied to analyze the H+ CH4 reaction. They addressed permutational symmetry by replicating data for permutations of the H atoms.[6] In contrast to this approach, the PIP method uses the linear least-square method to accurately match tens of thousands of electronic energies for both reactive and non-reactive systems mathematically.
Generally, the functions used in fitting potential energy surfaces to experimental and/or electronic structure theory data are based on the choice of coordinates. Most of the chosen coordinates are bond stretches, valence and dihedral angles, or other curvilinear coordinates such as the Jacobi coordinates or polyspherical coordinates. There are advantages to each of these choices. In the PIP approach, the N(N − 1)/2 internuclear distances are utilized. This number of variables is equal to 3N −6 (or 3N − 5 = 1 for diatomic molecules) for N = 3, 4 and differs for N ≥ 5. Thus, N = 5 is an important boundary that affects the choice of coordinates. An advantage of employing this variable set is its inherent closure under all permutations of atoms. This implies that regardless of the order in which atoms are permuted, the resulting set of variables remains unchanged. However, the main focus pertains to permutations involving identical atoms, as the PES must be invariant under such transformations.
PIP utilizing Morse variables of the form
yij=exp(-rij/a)
rij
i
j
a
Bowman is the author or co-author of more than 600 publications. He is an elected member of the International Academy of Quantum Molecular Sciences. He received the Herschbach Medal, which is the highest award given by the Conference on Molecular Collision Dynamics.[8] [9] He is an honorary fellow of the Chinese Chemical Society and an elected fellow of the American Physical Society[10] and of the American Association for the Advancement of Science.[1] In 2013, a Festschrift issue of the Journal of Physical Chemistry A was published in his honor.[11]