Feynman path centroid dynamics for Fermi-Dirac statistics

In this communication the centroid molecular dynamics (CMD) method is teste d for systems of fermions using a modified version of the expression for th e fermion Feynman path centroid density derived in a recent publication [J. Chem. Phys. 110, 3647 (1999)]. The method is applied to a model system con sisting of two noninteracting fermions in an anharmonic potential well and the position autocorrelation function is computed. The exact fermion positi on autocorrelation function exhibits a longer period of oscillation when co mpared to the bosonic case. This shift is due to the anharmonic nature of t he given potential function where the level spacing decreases with the incr ease of energy. The CMD results agree very well with the exact quantum mech anical results for this example. This indicates, along with the previous re sults on a boson system, that quantum statistics can in principle be incorp orated into the CMD method without any degradation of the accuracy of the a pproximation. (C) 1999 American Institute of Physics. [S0021-9606(99)50836- 2].