Hello,
A change in allocation has been requested:
Requester: bliu (Bin Liu)
Project: dft_biomass
Title: DFT studies of catalytic biomass conversion
Description: As part of the IACT (short for the Institute for Atom-efficient Chemical Transformations) supported by Energy Frontier Research Center at Argonne, the DFT calculations will be performed using the Vienna ab initio Simulation Program (VASP), which implements DFT in the periodic Bloch-type plane-wave, self-consistent Kohn-Sham framework. DFT studies conducted on Fusion cluster will focus on obtaining the thermodynamics and kinetics of the intermediate species derived from glycerol decomposition on Pt(111) and furfural hydrogenation on Pd(111) with an ultimate goal of constructing relevant free energy surfaces for their respective reaction network. In both cases, the research will involve a thorough investigation of the most stable adsorption configurations of the intermediate and searches for key transition states (using the Nudged Elastic Band algorithm) to obtain elementary reaction energy barriers. The computational demand of such investigation is substantial,
given the relatively large unit cells (either a 2 or 3-layer p(4x4) periodic slab) required, together with the large numbers of proposed reaction intermediates of interest (on the order of hundreds by considering all the possible intermediates). However, it is possible to reduce the computational workload by using insights gained from our preliminary investigations on the stable geometrical motifs of some of these intermediates, together with approximate yet useful correlations that can be used to estimate the binding energies and reaction energy barriers to make the work tractable and practical within the time requested (see below).
The classical MD simulations of amorphous alumina and zirconia on Fusion, although also being of great interest to the IACT, will require significantly less time than that requested for the DFT work; we estimate that 5-10% of the total computing time will be needed to run these classical MD simulations with DL-POLY (we have already verified the accuracy and suitability of our potentials with DL-POLY. These jobs will typically run on 4~8 Fusion nodes for large-scale production).
Dr. Bin Liu of CNM will be the primary invesitgator of this project with Dr. Jeff Greeley as the co-investigator. To complete the above work, we are requesting 600,000 core hours for FY2011. This is an estimate based on our preliminary work running on Fusion in the past 3 months, during which time approximately 120,000 core hours have been used. We anticipate that our need for Fusion resources will increase somewhat in the coming FY due an even greater level of scientific activity (the project has been ramping up but is now at steady state), as well as due to an oversubscription of other compute clusters (e.g., the Carbon cluster at the CNM).
Current: undetermined amount
Justification: Recent improvements in the parallelization of VASP combined with the improved hardware capabilities (e.g. the expanded memory) allow for reasonably efficient near-linear scaling for jobs running on up to 80 cores (10 nodes). Typically, a DFT job uses 4~8 nodes at a timescale of 48 hours. Furture usage will require larger number of nodes (8~10 nodes) due to a shift of our focus on transition state calculations. As the computation time for a single job of such calculation can be a week or even more. Large allocation is preferred to guarantee the completion of this investigation. In the mean time, we will efficiently use the requested allocation by carefully selecting the key reactions to produce outstanding science. We hope to continue to use Fusion cluster to satisfy our scientific interest.
Requested: 200000
A specific reason has been given:
The previous allocation has been devoted to thoroughly explore the adsorption configurations of glycerol intermediates and a selected number of glycerol decomposition pathways for BEP relationship. Although the search for stable configurations can be based on our chemical intuition and previous knowledge, certain variations can still lead to lower energy geometries, which consequently affects the NEB calculations. Due to this reason, we realized that our previous estimation is not enough to complete the study. Therefore, we request the above amount of allocation (200,000) for this FY. Thank you very much.
This needs to be approved and the final allocation amount decided upon.
Thank You,
The LCRC Accounts System
