Srinivasan Iyengar of Indiana University is supported by an award from the Chemical Theory, Models and Computational Methods program to continue the development of a combined quantum wavepacket molecular dynamics technique originally developed by the Iyengar group during the previous funding cycle. This work addresses one of the most challenging problems in modern theoretical chemical physics: the combined computational study of electronic structure and nuclear dynamics. QWAIMD involves the simultaneous dynamics of electrons and nuclei though the synergy of quantum wavepacket dynamics and ab initio molecular dynamics. It allows the computational implementation of a "self-contained black-box" technique for dynamics of electrons and nuclei that does not require a priori knowledge of the potential energy surface. These novel methods are being used to study the vibrational properties of hydrogen bonded clusters.
One of the most challenging issues in modern theoretical chemistry is determining the proper way to combine the inherently quantum mechanical description of the electrons in molecules with the description of molecular motion. Molecular motion is commonly treated using classical mechanics but in many cases quantum mechanical treatment is necessary. This work addresses the issue of how simultaneous quantum treatment of electrons and nuclei can be achieved. If successful, the work will have wide impact on the development of proper descriptions of a number of important application topics including hydrogen transfer reactions in biological enzyme systems, solvation assisted kinetics in atmospheric reactions and hydrogen transfer in fuel cells. The work is, thus, expected to have a broader impact in biology, atmospheric science and materials chemistry and, through the PI's extensive outreach work, on students from under-represented minorities.