Enhancing the Accuracy of Ab Initio Molecular Dynamics by Fine Tuning of Effective Two-Body Interactions: Acetonitrile as a Test Case

Citations Over TimeTop 23% of 2021 papers

Abstract

Grimme's dispersion-corrected density functional theory (DFT-D) methods have emerged among the most practical approaches to perform accurate quantum mechanical calculations on molecular systems ranging from small clusters to microscopic and mesoscopic samples, i.e., including hundreds or thousands of molecules. Moreover, DFT-D functionals can be easily integrated into popular ab initio molecular dynamics (MD) software packages to carry out first-principles condensed-phase simulations at an affordable computational cost. Here, starting from the well-established D3 version of the dispersion-correction term, we present a simple protocol to improve the accurate description of the intermolecular interactions of molecular clusters of growing size, considering acetonitrile as a test case. Optimization of the interaction energy was performed with reference to diffusion quantum Monte Carlo calculations, successfully reaching the same inherent accuracy of the latter (statistical error of ∼0.1 kcal/mol per molecule). The refined DFT-D3 model was then used to perform ab initio MD simulations of liquid acetonitrile, again showing significant improvements toward available experimental data with respect to the default correction.

Related Papers

• → Mesoscopic theory of liquid crystals(2004)16 cited
• → Mesoscopic Devices — What are They?(1995)1 cited
• → Electron Transport Through Mesoscopic Closed Loops and Molecular Bridges(2007)1 cited
• → Rock Mesoscopic Structural Plane, Mesoscopic Anisotropy and Mesoscopic Anisotropy Index(2012)
• → Review of Theory of Mesocopic Systems(2017)