Our main research tool in the Siepmann Group is MCCCS‒MN (Monte Carlo for Complex Chemical Systems‒Minnesota) which is under constant development. MCCCS‒MN allows the simulation of multicomponent chain systems in the canonical, isobaric-isothermal, grand-canonical, semi-grand, and Gibbs ensembles. It uses the configurational-bias Monte Carlo method to efficiently sample phase space for linear, branched and cyclic chain molecules, the adiabatic nuclear and electronic sampling Monte Carlo method to treat many-body polarization effects, and the aggregation-volume-bias Monte Carlo algorithm to efficiently sample the spatial distribution of associating molecules. A user-friendly version of this software (MCCCS‒Towhee), which implements the TraPPE force field along with several other common force fields, is maintained by Marcus G. Martin. It is available via a GNU general public license and can be downloaded from


The Car-Parrinello 2000 (CP2K) project is a collaborative effort of several international research groups (at ETH Zurich, Univ. of Zurich, Cambridge Univ., Lawrence Livermore Natl. Lab., Univ. of Minnesota). CP2K performs first principles (density functional theory) simulations in the microcanonical and canonical ensembles using molecular dynamics, or in the canonical, isobaric-isothermal, and Gibbs ensembles using Monte Carlo. The Siepmann group contributes to the on-going development of Monte Carlo algorithms within the CP2K program. While there has been no official release, the source code is freely available via the GNU general public license. The current version is available from