Computational Prediction of Kinetic Rate Constants

A core component of aerospace manufacturing is based on cutting-edge materials used in extreme environments. Chemical kinetics models are vital for interpreting experimental measurements and predicting the behavior of these complex systems. For many applications, the reaction rates for all required chemical processes are unknown. We propose a versatile user-friendly computational package for calculating chemical rate constants based on quantum chemistry, reaction dynamics, and transition state theory. This will be accomplished by enhancing the Extensible Computational Chemistry Environment (Ecce), a full-featured leading-edge graphical user interface, to incorporate kinetics calculations based on the quantum chemistry code NWChem, the dynamics code VENUS, and the transition state theory code POLYRATE. Together, they will enable the user to calculate rate constants from accurate quantum calculations within a single environment, while providing a realistic prediction of the inherent errors. In Phase I, our prototype package was successfully applied to a test case supplied by the AFOSR. In Phase II, we will fully integrate chemical rate constant predictions into Ecce forming the Ab initio Transition state Or Molecular dynamics Simulations for Chemical Rate Constants (ATOMS-CRC) Toolkit, advancing the state-of-the-art in simulations that are feasible on DoD chemical systems.