Hello, A change in allocation has been requested: Requester: coliu (Cong Liu) Project: Hetero_Catalysis Title: Development and Application of Accurate Theoretical Models for Calculating the Thermodynamics of Chemical Bonds for Heterogeneous Catalysis Description: Previously, we have studied CO2 reduction to CH3OH on alumina supported Cu4 clusters.[6] In the following year we will systematic studies of CO2 conversion to hydrocarbons using other Cu clusters (e.g., Cu3 and Cu20) supported on CNTs, graphene and aluminum oxide. The electronic and catalytic properties of the nanomaterials, metal-dependence, possible intermediates and transition states of the catalysis will be studied. These studies will provide crucial information for molecular insight into chemical reduction of CO2 and result in significant advancements in the development of novel efficient nanocatalysts. The following calculations will be performed: a. Gas-phase Cu3 and Cu20 clusters will be studied and compared to Cu4 cluster primarily to investigate the reaction mechanisms of CO2 reduction to C1-C2 hydrocarbons, as well as the size effects of the clusters. All possible reaction pathways will be calculated using DFT methods using the VASP package. All the intermediates, transition states and products will be explored. The proposed reaction paths will then be analyzed and compared from the thermodynamic point of view. The most likely reaction mechanism will be identified based on our calculations and the experimental observations. The electronic and energetic effects of the cluster size will be studied. These calculations are difficult, because the conformations of many of these metal clusters are unknown and first have to be identified using accurate DFT methods. These calculations will be carried out within both VASP and Gaussian09 packages. b. The catalytic properties of materials supported metal clusters will also be explored. CNTs, graphene and aluminum oxide will be considered as support materials. Interactions between the support materials and metal clusters and the effect of defects on CNTs and graphene will be calculated using DFT methods within VASP package. The simulation of defects on CNTs will begin with a two-dimensional graphene model, with replacements of carbon atoms by N and O. The partial charges of surrounding carbon atoms will be determined as a parameter to measure the charge transfer interactions. Then the interaction between the Cu clusters and CNTs will be studied. The interaction between the Cu clusters and aluminum oxide surfaces (hydroxylated) will be focused on the electron transfer interaction and the effect of the hydroxyl groups on the surface. c. Finally, based on the results in parts b and c, the best Cu catalyst will be identified for catalytic CO2 reduction. This will help the experimentalists better understand the details of the catalytic reaction and the role of the catalyst. Furthermore, insights to the effects of cluster size and support materials will be provided to guide experimental study by our collaborators. Based on this reaction mechanism, future computational studies will be carried out on different metal clusters (e.g., Co and Pt clusters) and metal alloy clusters. An assessment of the necessary calculations indicates that at least 400,000 core hours are necessary to complete this work. Current: undetermined amount Justification: Requested: 185000 A specific reason has been given: The DFT + U calculations are time consuming and more cpu hours are needed. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System