 Professor D.E. Manolopoulos
Physical & Theoretical Chemistry Laboratory
Telephone: 44 (0) 1865 275 164
Gas phase dynamics
Much of our research in the last ten years has focused on the
quantum mechanical description of elementary chemical reactions
in the gas phase. We have learned a great deal during this time
about the interpretation of transition state spectroscopy experiments,
the role of quantum mechanical resonances in hydrogen atom transfer
reactions, the significance of the non-adiabatic effects caused
by electronic and spin-orbit couplings, the effect of van der Waals
forces on chemical reaction dynamics, and the statistical nature
of insertion reactions that proceed via deep potential energy wells.
Condensed phase dynamics
We have recently shown how the standard path integral molecular
dynamics (PIMD) method, which has been used for the last twenty
years to compute the exact static equilibrium properties of quantum
mechanical systems, can be generalized to calculate approximate
real-time quantum correlation functions, and so used to study the
role of quantum mechanical (zero point energy and tunnelling) effects
in condensed phase chemical dynamics. The resulting ring-polymer
molecular dynamics (RPMD) method has already been applied to a
model for chemical reaction in solution and to the quantum diffusion
in liquid para-hydrogen, with encouraging results in both cases.
We are now planning to use the method to study a wider variety
of dynamical processes in both strongly quantum fluids like liquid
hydrogen and mildly quantum fluids like liquid water.
Selected recent publications
1. Quantum statistics and classical mechanics: Real time correlation
functions from ring polymer molecular dynamics. J. Chem. Phys. 121,
3368 (2004).
2. Chemical reaction rates from ring polymer molecular dynamics. J.
Chem. Phys. 122, 084106 (2005).
3. Quantum diffusion in liquid para-hydrogen from ring polymer
molecular dynamics. J. Chem. Phys. 122,
184503 (2005).
4. A refined ring polymer molecular dynamics theory of chemical
reaction rates. J. Chem. Phys. 123, 034102
(2005).
5. Quantum diffusion in liquid water from ring polymer molecular
dynamics. J. Chem. Phys. 123, 154504
(2005).
6. On the short time limit of ring polymer molecular dynamics. J.
Chem. Phys. 125, 124105 (2006).
7. Quantum mechanical correlation functions, maximum entropy
analytic continuation, and ring polymer molecular dynamics. J.
Chem. Phys. 127, 174108 (2007).
8. Proton transfer in a polar solvent from ring polymer reaction
rate theory. J. Chem. Phys. 128, 144502
(2008).
9. Quantum diffusion of hydrogen and muonium atoms in liquid
water and hexagonal ice. J. Chem. Phys. 128,
194506 (2008).
10. An efficient ring polymer contraction scheme for imaginary
time path integral simulations. J. Chem. Phys. 129,
024105 (2008). |
