Development and Application of Computational Methods for Investigating Proton-Coupled Electron Transfer Reactions
The quantum mechanical behavior of nuclei plays an important role in a wide range of chemical and biological processes. The inclusion of nuclear quantum effects and non-Born-Oppenheimer effects between nuclei and electrons in computer simulations is challenging. Our group has developed the nuclear-electronic orbital (NEO) method for treating electrons and select nuclei quantum mechanically on the same level using an orbital-based formalism. The NEO code utilizes a hybrid MPI/OpenMP protocol, but the calculations require a large number of processors and a substantial amount of memory. The highly parallel computing system on Blue Waters is advantageous for this code because it provides the capability of splitting the large number of calculations and storage requirements over many nodes. We have used Blue Waters to perform NEO calculations on systems in which all electrons and one proton are treated quantum mechanically and have tested approximate methods that enable the study of larger systems.