We present a parallel implementation of the Fourier Path Integral Monte Carlo method for calculating the absolute free energies of many-body systems. The implementation adopts the message-passing paradigm for parallelization, with the use of the Message Passing Interface (MPI) libraries. A portable computer program, written using Fortran 90, has been developed and tested on a variety of platforms such as the SGI Origin, the IBM SP, and the Cray T3D and T3E. We have used the program to demonstrate the efficacy of importance sampling in configuration space. We have also used the program to calculate the partition function, and hence the absolute free energies, of triatomic molecules and four-body systems.
Bibliographical noteFunding Information:
We thank Yao-Yuan Chuang for helpful discussions. This work was supported in part by the National Science Foundation under grant no. CHE97-25965.