Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Rees Rankin Project Name: DFT_TM_Catal_Screen Division: CNM Project title: DFT Screening Investigation on Catalytic and Electrocatalytic Phenomena of Transition Metals Associated funding: LDRD-$ and Basic Sciences Other Systems: Carbon compute cluster @ CNM here at ANL Science: In this project, we will expand on successful previous efforts (FY2009,FY2010) to utilize the Density Functional Theory (DFT) framework to determine the geometry and associated energy(ies) of molecular reactants, intermediate moieties (e.g. reaction intermediates, and products) on the exposed surfaces of transition metals (TM ). By obtaining such properties, we can derive understanding that serves dual purposes. First, we can directly calculate the potential energy, and hence the free energy of reaction mechanisms of interest on these TM surfaces- whether they be ideal defect free surfaces (flat 111 type surfaces) or step type surfaces which represent the more reactive sites on realistic nanoparticles. Second, we can further populate our database of computational catalytic properties which will be used for predictive screening of additional reactions, catalysts, and products via interpolative schemes and Sabatier Volcano type analysis through previously determine d (and calculated) descriptors. This is particularly relevant when considering catalyst design involving multiple atomic species, such as in the case of binary or ternary alloys. These materials are of great interest for future catalytic needs for reasons of improved catalytic efficiency, product (de)selectivity, and economic viability. Project description: In the previous work in FY2009 and 2010 we performed DFT calculations to begin to study an important reaction in the context of fundamental heterogeneous catalytic as well as electrocatalytic applications, as well as build our computational database and Sabatier Volcano analytical methods. Specifically, this reaction involved the selective reduction of molecular oxygen (O2) by TM catalysts to hydrogen peroxide (H2O2). The applications of studying this reaction were numerous. It is well known that H2O2 historically has not been synthesized efficiently via direct conversion of H2 and O2. Recent work in the literature suggests metallic alloy nanoparticles can create new chemistry in the selective synthesis of H2O2 from H2 and O2. After completing our initial work (flat, and stepped surfaces of 'pure' single component TM species) on this reaction in FY2009/FY2010, we have begun initial work towards similar studies using the same methods to characterize selective product reactions in the electrochemical reduction of CO2 (CDR) towards more economically and environmentally beneficial target species. Compared to the previous work on H2O2 this is a much more complex reaction network to study (with more paths and branchpoints) that requires significantly more calculations of potential descriptors and transition states to determine the appropriate Sabatier Volcano relations. However, by building on the knowledge generated from such studying such critical, and fundamental reactions, it will be much more feasible to predict the performance of novel catalysts in other reactions which involve the same or similar reactants and intermediates but different products, or conversely, differing reactants with similar intermediates and products. Our work will continue to supplement the computational materials-by-design and Materials Design Workbench database being developed. The results of populating the MDW database will allow far great er amounts of materials and catalyst reactions to be quickly predictively screened in the future. Calculations will be expected to be performed using the Vienna ab initio Simulation Program (VASP). This program , currently deployed on Fusion, uses a periodic plane-wave representation of the electronic wavefunctions of materials with a self-consistent minimization/solution under the Density Functional Theory (DFT) formalism. Recent improvements in the parallelization of VASP combined with the excellent parallel hardware capabilities in the LCRC Fusion system allow for reasonably efficient near-linear scaling for jobs running on up to ~ 80 cores (10 nodes). Superlinear scaling can occasionally now even be seemingly witnessed for small jobs in a single compute node with appropriate cache sizes. Additional calculations in the future may utilize the Dacapo DFT code, which performs similarly to VASP in the above regards Ongoing and previous calculations for this work have already been performed on the HPC Carbon cluster available at the CNM (ANL), and the Fusion system at LCRC (ANL) in FY2009/FY2010, and are continuing into FY2011. However, the resources available at CNM-ANL Carbon cluster are currently significantly overloaded even after the recent hardware expansion; small scale jobs can actually sit in the submission queue for time intervals longer than their execution related wall time. An allocation of 750k core hours on LCRC-Fusion would ostensibly allow for approximately 1800 calculation-sets (1 calculation-set here can be envisioned as scanning several related materials (such as differently structured surface alloys of the same stoichiometry) + adsorbate over many adsorption sites, or scanning a single material surface +adsorption site over many adsorbates, or as a series of coupled calculations to determine the transition state/activation energy between two local minima). The abil ity to augment our knowledge base with the incorporation of this many additional calculation-sets would be paramount in developing the detailed understanding necessary to move forward in a purely computational catalysis by design (or broader materials by design) project. As a note, we used essentially all of our FY2010 Allocation of 650k hours effectively in ~8-9 months, and we propose to do effectively the same the number of total calculations in FY2011 now that we have a detailed initial understanding of our methods and some basic insights into fundamental reaction mechanisms/TM species we wish to study in vastly greater detail. The availability of high performing computing resources such as Fusion will greatly augment our calculation possibilities and accelerate understanding of our Sabatier relations for the CDR reaction and simultaneously help us continue populating our computational catalysis database. Project URL: Current FY Hours Used: undetermined amount New FY Requested allocation: 750000 Justification: As a brief summary of typical results, Vasp 4.6 or Vasp 5.x+ with appropriate compilation, Infiniband, and modern processor cores scales well (near linear) out to approximately 80 cores or 10 (Fusion) nodes for most typical calculations on these similar HPC systems. VASP scaling does fall significantly in the regime of calculations with severely large file I/O overhead--however, this is not expected to apply to the jobs performed in the proposed work. We can provide sample benchmarks representative of the type of scaling efficiency our typical calculations have achieved to date on Fusion nodes if necessary. Thank You, The LCRC Accounts System