Roberto Car of Princeton University is supported by an award from The Theory, Models and Computational Methods program to develop new theoretical and computational enhancements of ab-initio molecular dynamics (AIMD) simulations with special focus on applications to water and hydrogen-bonded systems. The PI and his research group focus on a four-pronged strategy: (i) simulations based on more accurate electronic density functional with inclusion of dispersion forces will be made possible, (ii) the potential experienced by the protons participating in hydrogen bonds will be unearthed by utilizing a novel theoretical concept that allows unprecedented comparison of quantum simulations and deep inelastic neutron scattering data, including already performed and newly planned experiments, (iii) a new real space scheme will be implemented to compute core and valence electronic excitations with accurate many-body methods (e. g. the GW approximation and the Bethe-Salpeter equation) for systems with hundreds of atoms at selected snapshots of AIMD simulations, boosting comparison with experiments (X-rays, UV and optical spectra) and their interpretation, and (iv) the affinity of hydrophobic interfaces for water ions will be computed with thermodynamic integration techniques, advancing the understanding at the molecular level of processes of great scientific and technological relevance.
The project will contribute to the scientific infrastructure with new algorithms for molecular simulation and spectral calculation, which will be made available to the wider science and engineering community through the open software platforms Quantum Espresso and Car-Parrinello Molecular Dynamics. The educational component of this project is well integrated with the proposed research.
