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Published on: December 4, 2017
Complex-time velocity autocorrelation functions for Lennard-Jones fluids with quantum pair-product propagators
Jeb Kegerreis1, Akira Nakayama, Nancy Makri
1Department of Chemistry, University of Illinois, 601 S. Goodwin Avenue, Urbana, IL 61801, USA.
Abstract:
We use the pair-product approximation to the complex-time quantum mechanical propagator to obtain accurate quantum mechanical results for the symmetrized velocity autocorrelation function of a Lennard-Jones fluid at two points on the thermodynamic phase diagram. A variety of tests are performed to determine the accuracy of the method and understand its breakdown at longer times. We report quantitative results for the initial 0.3 ps of the dynamics, a time at which the correlation function has decayed to approximately one fifth of its initial value.
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