Automated Workflow for Redox Potentials and Acidity Constants Calculation from Machine Learning Molecular Dynamics

Authors

Feng Wang, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen 361005, Fujian, China
Jun Cheng, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen 361005, Fujian, China; Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China; Tan Kah Kee Innovation Laboratory, Xiamen 361005, Fujian, China

Document Type

Protocol

Corresponding Author(s)

Jun Cheng (juncheng@xmu.edu.cn)

Abstract

Redox potentials and acidity constants are key properties for evaluating the performance of energy materials. To achieve computational design of new generation of energy materials with higher performances, computing redox potentials and acidity constants with computational chemistry have attracted lots of attention. However, lots of works are done by using implicit solvation models, which is difficult to applied to complex solvation environments due to hard parameterization. Recently, ab initio molecular dynamics (AIMD) has been applied to investigate real electrolytes with complex solvation. Furthermore, AIMD based free energy calculation method have been established to calculate these physical chemical properties accurately. However, due to the low efficiency of ab initio calculations and the high computational costs, AIMD based free energy calculation are limited to systems with less than 1000 atoms. To solve the dilemma, machine learning molecular dynamics (MLMD) is introduced to accelerate the calculations. By using machine learning method to construct one-to-one mapping from structures to computed potential energies and atomic forces, molecular dynamics can be carried out with much low costs under ab initio accuracy. In order to achieve the MLMD based free energy calculation, a new scheme for machine learning potential (MLP) should be introduced to collect training datasets. By combining the free energy perturbation sampling method and concurrent learning scheme, the training datasets can be collected along the reaction’s pathway (insertion of an electron or a proton) with high efficiency and the free energy calculation based on MLMD show good accuracy in comparison with AIMD simulation. This paper describes how to constructing machine learning potential for free energy calculation through the automated workflow and how to use MLMD to compute accurate free energy differences and corresponding physical chemical properties.

Graphical Abstract

Keywords

machine learning molecular dynamics, automated workflow, complex systems, free energy calculation

DOI

10.13208/j.electrochem.2307181

Online Date

11-6-2023

Recommended Citation

Feng Wang, Jun Cheng. Automated Workflow for Redox Potentials and Acidity Constants Calculation from Machine Learning Molecular Dynamics[J]. Journal of Electrochemistry, doi: 10.13208/j.electrochem.2307181.