Gregory Sion Ezra

Overview

Professor Ezra's research covers many aspects of dynamics in chemistry and physics. He is interested in the role of symmetry in physical problems, in classical, semi-classical and quantum approaches to atomic and molecular systems, and in geometrical aspects of Hamiltonian and non-Hamiltonian dynamics.

Research Focus

Our research is concerned with the bound state and reaction dynamics of molecular and atomic systems. Processes of interest include intramolecular vibrational energy transfer, unimolecular dissociation, and collisional energy transfer. Classical trajectory methods, semiclassical theories, and direct solution of the nuclear Schrodinger equation are employed as appropriate to investigate fundamental problems in intramolecular and collision dynamics. We are also interested in novel semiclassical approaches to the characterization of highly excited states of few-body Coulomb systems.

A central aim of our work is a detailed understanding of intramolecular energy flow and its consequences for spectroscopy and chemical kinetics. In particular, we seek chemically useful correlations between the shape of a molecular potential energy surface and the associated reactive and bound-state dynamics. Another basic theme of our work is the relation between the classical and quantum mechanics of systems of chemical interest such as molecular Hamiltonians or multielectron atoms.

Publications

Publications (full list)

• Index k saddles and dividing surfaces in phase space, with applications to isomerization dynamics,

P. Collins, G. S. Ezra and S. Wiggins, J. Chem. Phys. 134, 244105 (2011)

• Isomerization kinetics of a strained Morse oscillator ring,

J. N. Stember and G. S. Ezra, Chem. Phys. 381, 80-87 (2011)

• Algorithms for non-Hamiltonian dynamics,

A. Sergi and G. S. Ezra, Atti Accad. Pelorit. Pericol. Cl. Sci. Fis. Mat. Nat., Vol. LXXXVIII, No. 2, C1C1002002 (2010)

• Phase space geometry and reaction dynamics near index two saddles,

G. S. Ezra and S. Wiggins, J. Phys. A 42, 205101 (2009)

• Microcanonical rates, gap times, and phase space dividing surfaces,

G. S. Ezra, H. Waalkens and S. Wiggins, J. Chem. Phys.130, 164118 (2009)

• Fragmentation kinetics of a Morse oscillator chain under tension,

J. N. Stember and G. S. Ezra, Chem. Phys. 337, 11-32 (2007)

• Reversible measure-preserving integrators for non-Hamiltonian systems,

G. S. Ezra, J. Chem. Phys. 125, Art. No. 034104 (2006).

• Quantum monodromy for diatomic molecules in combined electrostatic and pulsed nonresonant laser fields,

C. A. Arango, W. W. Kennerly, and G. S. Ezra, Chem. Phys. Lett. 392, 486-492 (2004).

• On the statistical mechanics of non-Hamiltonian systems: the generalized Liouville equation, entropy, and time-dependent metrics,

G. S. Ezra, J. Math. Chem. 35, 29-53 (2004).

• Optical response functions with semiclassical dynamics,

W. G. Noid, G. S. Ezra, and R. F. Loring, J. Chem. Phys. 119, 1003-1020 (2003).

CHEM Courses - Spring 2025

• CHEM 3900 : Honors Physical Chemistry II
• CHEM 6900 : Honors Physical Chemistry II

CHEM Courses - Fall 2025

• CHEM 3890 : Honors Physical Chemistry I
• CHEM 6890 : Honors Physical Chemistry I