Automated development of force fields for the calculation of thermodynamic properties: acetonitrile as a case study

Abstract

Force fields for engineering applications are often parameterised using strategies based on quantum mechanical ab initio calculations and thermodynamic properties from experiment. An automated procedure for adjusting molecular model parameters to experimental thermodynamic property data is introduced. The process accelerates the development of molecular models by an efficient use of parallel computing power and an autonomous progress of the model development without any user interaction. As a case study, the procedure is applied to the parameterisation of a molecular model for acetonitrile. The resulting model reproduces vapour–liquid equilibrium data of acetonitrile with an accuracy of 0.1% for the saturated liquid density, 4.9% for the vapour pressure and 3.7% for the enthalpy of vaporisation. These accuracies are superior to data obtained with previously published force fields for acetonitrile.

Keywords:

• molecular modelling
• force field
• optimisation
• automation
• acetonitrile

Acknowledgements

The authors gratefully acknowledge financial support by the BMBF ‘01H08013A – Innovative HPC-Methoden und Einsatz für hochskalierbare Molekulare Simulation’ and computational support by the Steinbuch Centre for Computing under the grant MOCOS and the High Performance Computing Center Stuttgart (HLRS) under the grant MMHBF2. The present research was conducted under the auspices of the Boltzmann-Zuse Society of Computational Molecular Engineering (BZS).

Notes

^1. http://www.crontab.org

^2. The MathWorks, Inc. Natick, MA US