ms2: A molecular simulation tool for thermodynamic properties, release 4.0

A new version release (4.0) of the molecular simulation tool ms2 (Deublein et al. 2011; Glass et al. 2014; Rutkai et al. 2017) is presented. Version 4.0 of ms2 features two additional potential functions to address the repulsive and dispersive interactions in a more versatile way, i.e. the Mie potential and the Tang-Toennies potential. This version further introduces Kirkwood-Buff integrals based on radial distribution functions, which allow the sampling of the thermodynamic factor of mixtures with up to four components, orientational distribution functions to elucidate mutual configurations of neighboring molecules, thermal diffusion coefficients of binary mixtures for heat, mass as well as coupled heat and mass transport, Einstein relations to sample transport properties with an alternative to the Green-Kubo formalism, dielectric constant of non-polarizable fluid models, vapor-liquid equilibria relying on the second virial coefficient and cluster criteria to identify nucleation. New version programm summary Program Title: ms2 Program Files doi: http://dx.doi.org/10.17632/nsfj67wydx.3 Licensing provisions: CC by NC 3.0 Programming language: Fortran95 Supplemental material: A detailed description of the parameter setup for the introduced methods, properties, functionalities etc. is given in the supplemental material. Furthermore, all molecular force field models developed by our group are provided by the MolMod Database: Stephan et al., Mol. Sim. 45 (2019) 806 Journal reference of previous version: Deublein et al., Comput. Phys. Commun. 182 (2011) 2350 and Glass et al., Comput. Phys. Commun. 185 (2014) 3302 and Rutkai et al., Comput. Phys. Commun. 221 (2017) 343 Does the new version supersede the previous version: Yes Reasons for the new version: Introduction of new features as well as enhancement of computational efficiency Summary of revisions: Two new potential functions to address repulsive and dispersive interactions (Mie and Tang-Toennies potential), new properties (Helmholtz energy, Kirkwood-Buff integrals, thermodynamic factor, thermal diffusion coefficients, dielectric constant, mean squared displacement and non-Gaussian parameter), new functionalities (Kirkwood-Buff integration with extrapolation to the thermodynamic limit, van der Vegt correction for the radial distribution function, orientational distribution function, Einstein relations, vapor-liquid equilibria estimations, cluster criteria to identify nucleation). Nature of problem: Calculation of application-oriented thermodynamic properties: vapor-liquid equilibria of pure fluids and multi-component mixtures, thermal, caloric and entropic data as well as transport properties and data on microscopic structure Solution method: Molecular dynamics, Monte Carlo, various ensembles, Grand equilibrium method, Green-Kubo formalism, Einstein formalism, Lustig formalism, OPAS method, smooth-particle mesh Ewald summation. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The new version 4.0 of the molecular simulation tool ms2 introduces two additional potential functions and enhances computational efficiency. It also provides new properties, functionalities, and features, such as thermodynamic factor, thermal diffusion coefficients, and non-Gaussian parameters, to improve the application-oriented thermodynamic properties and microscopic structure analysis.