We have written our own Monte Carlo code for the primary purpose of simulating gas adsorption in Metal-Organic Frameworks. Although, there are other MC codes freely available, to our knowledge, none are compatible with the use of polarizable force fields. Although the code is fairly versatile, it is primary designed to be used with our SAPT-based force fields, such as “SYM” (.itp files available below) and “ZIF FF” , and thus utilizes a hybrid MD/MC algorithm to allow for the efficient simulation of polarizable solute gas molecules. It incorporates shared memory level parallelization (OpenMP), as well as accurate and efficient treatments of long-range electrostatics and dispersion through a Particle-Mesh Ewald treatment of both types of forces.
We have also written a lattice model code, that can be used to calculate gas adsorption isotherms in nano-porous materials while significantly reducing the computational time compared to standard GCMC simulations. In addition to calculating isotherms, the lattice model naturally generates a spatial free energy grid of the material, which can also be useful to visualize important adsorption sites.
The source codes are freely available for download. The codes are written in Fortran 90, and requires select MKL libraries for Discrete Fourier Transforms, as well as libraries used in the OpenMP parallelization. Included in the tar download file is the source code, a brief code manual, several examples, “clean” crystal structures of select ZIFs that we have studied, and published force field parameters for the “SYM” and “ZIF FF” force fields.
We request that anyone who publishes results that utilize either the code and/or force fields cite the appropriate references listed below:
“SYM” force field:
Yu, K.; McDaniel, J. G.; Schmidt, J. R. J. Phys. Chem. B 2011, 115, 10054-10063.
Yu, K.; Schmidt, J. R. J. Chem. Phys. 2012, 136, 34503-34509.
“ZIF FF” force field:
McDaniel, J. G.; Schmidt, J. R. J. Phys. Chem. C 2012, 116, 14031-14039.
McDaniel, J. G.; Schmidt, J. R. J. Phys. Chem. A 2013, 117, 2053-2066.
Hybrid MD/MC code:
McDaniel, J. G.; Yu, K.; Schmidt, J. R. J. Phys. Chem. C 2011, 116, 1892-1903.
Lattice Model code:
Yu, K.; McDaniel, J. G.; Schmidt, J. R. J. Chem. Phys. 2012, 137, 244102.
We welcome suggestions and comments on how we could make our code more “user friendly”, or make our force fields more readily implemented.
DOWNLOAD Monte Carlo/Lattice model codes
(download last updated 1/20/2015)