Abstract
The most commonly used short time propagator in a discretized Feynman path integral (and also several more sophisticated "improved" ones) is not correct through first order in the time increment Δt. The correct result for the phase (i.e. the action) of the short time propagator is developed in this paper as a power series in Δt, explicit expressions being given for the terms of order Δt-1, Δt, and Δt3. Test applications to the standard harmonic oscillator and also to a double well potential (typical for intramolecular H-atom transfer) show the first-order propagator (i.e. the correct result through order Δt) to be a significant improvement over previous ones; inclusion of the third-order term gives considerable additional improvement (i.e. faster convergence).
Original language | English (US) |
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Pages (from-to) | 1-8 |
Number of pages | 8 |
Journal | Chemical Physics Letters |
Volume | 151 |
Issue number | 1-2 |
DOIs | |
State | Published - Oct 7 1988 |
Externally published | Yes |
ASJC Scopus subject areas
- General Physics and Astronomy
- Physical and Theoretical Chemistry