A Comparison of Advanced Monte Carlo Methods for Open Systems: CFCMC vs CBMC

Two state-of-the-art simulation methods for computing adsorption properties in porous materials like zeolites and metal-organic frameworks are compared: the configurational bias Monte Carlo (CBMC) method and the recently proposed continuous fractional component Monte Carlo (CFCMC) method. We show that CFCMC is a very significant improvement over CBMC, and we can recommend it as our preferred method of choice. It is faster, more reliable, and (in contrast to CBMC) provides insight on whether or not the results are properly equilibrated. We also show that it is possible to combine the methods in a new CB/CFCMC hybrid method and derive the acceptance rules. This method achieves even higher insertion acceptance ratios.