Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Aslihan Sumer Project Name: Comp_Nanocatalysis Division: CSE Project title: Theoretical/Computational Studies of the Fundamentals of One-Component and Alloy Metal Based Nanocatalysis Relevant to Alternative Sources of Energy Associated funding: BES/DOE Other Systems: NERSC, ~1000000 core-hours Science: The central objective of this project is to perform modeling and computational studies that aim at understanding and characterization of the chemical reactivity and catalytic functionality of pure and alloy metal nanoparticles at the microscopic (i.e., atomic and electronic) level. Atomic and molecular nanoparticles and related systems and phenomena are the subject of a rapidly developing research field in catalysis, owing to the unique properties of these materials at different sizes, conformation and compositions. The complexity of these systems, arising from the multiplicity and variety of their structural forms and the reactive sites, offer a large number of questions which are hardly explored in catalysis. We particularly aim to address the factors that govern the preferred morphology and the role of morphology in controlling catalytic functionality, through computations within the density functional framework (DFT). Project description: The changes in the electronic structure of metal nanoparticles as a result of charge addition or depletion can lead to changes in the morphology of metal nanoparticles. Last year, through a collaborative approach with Dr. André Fielicke and his spectroscopy group at Fritz-Haber Institute, Germany, we studied the relations between the morphology, electronic structure and charge state of sub-nano size platinum particles (n=2-13 atoms). The computations reproduced the experimental findings of spectroscopy (performed on anionic and neutral Pt clusters) at an accuracy exceeding the literature and reveals important information on the electronic and physical transformations during charge transfer in platinum clusters. The collaborative approach validated our computational method and proved its suitability to other metal clusters involved in specific catalytic reactions. This year we plan to expand the scope of our work to Pd nanoparticles. Palladium nanoparticles are important for many applications such as catalysis, hydrogen storage and sensors. We plan to map out the potential energy surface for Pd nanoparticles (n=3-26 atoms) at neutral and anionic states to determine the minimum energy structures and optimum spin states using DFT. In a parallel fashion, spectroscopic experiments will be performed and the observed charge distributions and ionization potentials will be correlated with the computational results. There are a number of published papers in literature on the stable isomeric forms of Pd clusters. However the majority of these studies focus on the neutral states of the structures and how charge addition/depletion affects the morphology still is under investigation, particularly at relatively larger sizes. We will re-optimize the geometrical arrangements reported in the literature at neutral and anionic states. To determine the preferred structural arrangement of Pd atoms at relatively larger sizes (i.e. n>13 atoms), we plan to take advantage of the simulated annealing module of NWChem to further expand our database of stable Pd isomeric forms. The project members are Julius Jellinek and Aslihan Sumer. For the next year, we are planning to use VASP, NWchem, CP2K and Crystal09 softwares to model and study the systems of interest. These codes offer high scaling efficiency and advanced methodological capabilities, e.g. availability of high-level exchange-correlation functionals and dispersion corrections, which we will take advantage of to deal with the increased complexity of our models. Industry partnership: Project URL: Current FY Hours Used: undetermined amount New FY Requested allocation: 800000 Q1: 200000 Q2: 200000 Q3: 200000 Q4: 200000 Justification: The allocation request is based on previous DFT test runs with NWChem and VASP on LCRC and NERSC clusters. Scaling efficiency of parallel computations with NWChem and VASP are overall high. Tests for with NWChem on Blues and Nersc systems using various number of processors show a substantial increase in performance with the increase in the number of processors up to hundreds of processors: Pt7-glycerol-water complex (77 atoms and total of 469 basis functions) optimized with NWchem on Blues: Cores Average SCF cycle (s) 64 9 128 6 Pt7-glycerol system (20 atoms and total of 544 basis functions) optimized with NWChem on Nersc/Edison: Cores Average SCF cycle (s) 120 15 240 9 Storage requirements: 1 TB (default) Thank You, The LCRC Accounts System