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Shi BX, Kapil V, Zen A, Chen J, Alavi A, Michaelides A. General embedded cluster protocol for accurate modeling of oxygen vacancies in metal-oxides. J Chem Phys 2022; 156:124704. [DOI: 10.1063/5.0087031] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The O vacancy (Ov) formation energy, EOv, is an important property of a metal-oxide, governing its performance in applications such as fuel cells or heterogeneous catalysis. These defects are routinely studied with density functional theory (DFT). However, it is well-recognized that standard DFT formulations (e.g., the generalized gradient approximation) are insufficient for modeling the Ov, requiring higher levels of theory. The embedded cluster method offers a promising approach to compute EOv accurately, giving access to all electronic structure methods. Central to this approach is the construction of quantum(-mechanically treated) clusters placed within suitable embedding environments. Unfortunately, current approaches to constructing the quantum clusters either require large system sizes, preventing application of high-level methods, or require significant manual input, preventing investigations of multiple systems simultaneously. In this work, we present a systematic and general quantum cluster design protocol that can determine small converged quantum clusters for studying the Ov in metal-oxides with accurate methods, such as local coupled cluster with single, double, and perturbative triple excitations. We apply this protocol to study the Ov in the bulk and surface planes of rutile TiO2 and rock salt MgO, producing the first accurate and well-converged determinations of EOv with this method. These reference values are used to benchmark exchange–correlation functionals in DFT, and we find that all the studied functionals underestimate EOv, with the average error decreasing along the rungs of Jacob’s ladder. This protocol is automatable for high-throughput calculations and can be generalized to study other point defects or adsorbates.
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Affiliation(s)
- Benjamin X. Shi
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Venkat Kapil
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Churchill College, University of Cambridge, Storey’s Way, Cambridge CB3 0DS, United Kingdom
| | - Andrea Zen
- Dipartimento di Fisica Ettore Pancini, Università di Napoli Federico II, Monte S. Angelo, I-80126 Napoli, Italy
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Ji Chen
- School of Physics, Peking University, Beijing 100871, China
| | - Ali Alavi
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Angelos Michaelides
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
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2
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Rybakov AA, Todorova S, Trubnikov DN, Larin AV. Reconstruction and catalytic activity of hybrid Pd(100)/(111) monolayer on γ-Al 2O 3(100) in CH 4, H 2O, and O 2 dissociation. Dalton Trans 2021; 50:8863-8876. [PMID: 34100496 DOI: 10.1039/d1dt01345a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The importance of the "heterogeneity" of a Pd monolayer induced by interaction with a semi-ionic support in catalysis was evaluated. The geometry of the Pd monolayer was optimized on the (100) plane of γ-Al2O3 at fixed unit cell parameters defined by the oxide. Simulation of the deposition of a whole Pd monolayer in the flat Pd(100) form cut from the bulk led to the formation of a slightly distorted Pd(111) monolayer. The subsequent chemisorption or dissociation of CH4 or H2O on the Pd(111) layer resulted in a new hybrid Pd(100)/(111) structure containing alternating elements of (100) and (111) planes (the parallel bands of squares and triangles), which are similar for both CH4 and H2O reactions, and two isolated Pd mono-vacancies, respectively. The hybrid Pd(100)/(111) layer without chemisorbed species was found to be more stable than the initial distorted Pd(111) layer. The catalytic capabilities of these monolayer structures were investigated for the dissociation of methane and the water-gas shift reaction (WGSR) due to the lower predicted activation barriers for CH4, H2O, and O2 dissociation on the hybrid Pd(100)/(111) layer compared to that on the pure (bulk) Pd(100) surface. Moreover, the exothermic heats of these reactions were calculated to be moderate instead of endothermic heats on the Pd(100) or Pd(111) surfaces. The heats of H2O and NH3 adsorption on various monolayers were tested, revealing their dependence on Pd atomic charges. The relevance of the model of the heterogeneous Pd monolayer for explaining the maximum reaction rate experimentally observed at different Pd coverages was discussed. The transferability of the geometry and the extent of charge inhomogeneity of the hybrid monolayer without vacancies were also tested on the same γ-Al2O3(100) support for Pt, Rh, and Ag.
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Affiliation(s)
- A A Rybakov
- Department of Chemistry, Moscow State University, GSP-2, Leninskie Gory, Moscow 119992, Russia.
| | - S Todorova
- Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Bldg 11, 1113 Sofia, Bulgaria
| | - D N Trubnikov
- Department of Chemistry, Moscow State University, GSP-2, Leninskie Gory, Moscow 119992, Russia.
| | - A V Larin
- Department of Chemistry, Moscow State University, GSP-2, Leninskie Gory, Moscow 119992, Russia.
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3
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Kuklja MM, Tsyshevsky R, Zverev AS, Mitrofanov A, Ilyakova N, Nurmukhametov DR, Rashkeev SN. Achieving tunable chemical reactivity through photo-initiation of energetic materials at metal oxide surfaces. Phys Chem Chem Phys 2020; 22:25284-25296. [PMID: 33136098 DOI: 10.1039/d0cp04069j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Known applications of high energy density materials are impressively vast. Despite this, we argue that energetic materials are still underutilized for common energy purposes due to our inability to control explosive chemical reactions releasing energy from these materials. The situation appears paradoxical as energetic materials (EM) possess massive amounts of energy and, hence, should be most appropriate for applications in many energy-intensive processes. Here, we discover how chemical decomposition reactions can be stimulated with laser excitation and therefore, highly controlled by selectively designing energetic material - metal oxide interfaces with an example of pentaerythritol tetranitrate (PETN)-MgO and trinitrotoluene (TNT)-MgO composite samples. Density functional theory and embedded cluster method calculations were combined with measurements of the optical absorption spectra and laser initiation experiments. We found that the first (1064 nm, 1.17 eV), second (532 nm, 2.33 eV), and third (355 nm, 3.49 eV) laser harmonics, to all of which pure energetic materials are transparent, can be effectively used to trigger explosive reactions in the PETN-MgO samples. We propose a consistent electronic mechanism that explains how specific sub-band optical transitions initiate decomposition chemistry. Also, this selectivity reveals a fundamental difference between materials chemistry at interfaces as we show on examples of PETN and TNT energetic materials.
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Affiliation(s)
- Maija M Kuklja
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.
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4
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Qin R, Liu K, Wu Q, Zheng N. Surface Coordination Chemistry of Atomically Dispersed Metal Catalysts. Chem Rev 2020; 120:11810-11899. [DOI: 10.1021/acs.chemrev.0c00094] [Citation(s) in RCA: 171] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ruixuan Qin
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Kunlong Liu
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Qingyuan Wu
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Nanfeng Zheng
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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5
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Chen S, Liang S, Wu B, Lan Z, Guo Z, Kobayashi H, Yan X, Li R. Ultrasmall Silver Clusters Stabilized on MgO for Robust Oxygen-Promoted Hydrogen Production from Formaldehyde Reforming. ACS APPLIED MATERIALS & INTERFACES 2019; 11:33946-33954. [PMID: 31462039 DOI: 10.1021/acsami.9b11023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Efficient molecular hydrogen generation from renewable biomass-derived resources and water is of great importance to the sustainable development of the future society. Herein, ultrasmall Ag nanoclusters supported on a defect-rich MgO matrix (AgUCs/MgO) are synthesized by a facile impregnation/calcination method and are applied to robust oxygen-promoted formaldehyde reforming into H2 at room temperature. Density functional theory calculations and experimental observations show that the catalyst spatially builds up a channel for directional electron transfer from electron-rich Ag sites to the anti-bonding π orbital of chemisorbed bridged O2 molecules, leading to the implementation of low-temperature O2 adsorption and activation. The catalytically active species, •OOH, is thus selectively generated via a preferential two-electron reduction of O2 with a low energy barrier on Ag sites, involving an unusual long-range proton-coupled electron transfer process. The •OOH-AgUCs/MgO active center is efficient for the subsequent C-H activation and H2 generation, leading to a 3-fold improvement of the turnover frequency as compared with its analogous AgNPs/MgO catalyst. Our atomic-level design and synthetic strategy provide a platform that facilitates the construction of an electron-proton transfer channel for catalysis, altered adsorption configurations of activated reactants, and enhancement of catalytic hydrogen generation activity, extending a promising direction for the development of next-generation energy catalysts.
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Affiliation(s)
- Shuang Chen
- Department of Materials Engineering, College of Material and Textiles , Zhejiang Sci-Tech University , Hangzhou 310018 , China
| | - Shipan Liang
- Department of Materials Engineering, College of Material and Textiles , Zhejiang Sci-Tech University , Hangzhou 310018 , China
| | - Biling Wu
- Department of Materials Engineering, College of Material and Textiles , Zhejiang Sci-Tech University , Hangzhou 310018 , China
| | - Zhuohuang Lan
- Department of Materials Engineering, College of Material and Textiles , Zhejiang Sci-Tech University , Hangzhou 310018 , China
| | - Ziwei Guo
- Department of Materials Engineering, College of Material and Textiles , Zhejiang Sci-Tech University , Hangzhou 310018 , China
| | - Hisayoshi Kobayashi
- Emeritus Professor of Department of Chemistry and Materials Technology , Kyoto Institute of Technology , Matsugasaki , Sakyo-ku, Kyoto 606-8585 , Japan
| | - Xiaoqing Yan
- Department of Chemistry, College of Science , Zhejiang Sci-Tech University , Hangzhou 310018 , China
| | - Renhong Li
- Department of Materials Engineering, College of Material and Textiles , Zhejiang Sci-Tech University , Hangzhou 310018 , China
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6
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Töpfer K, Tremblay JC. First-Principle Investigations of the Interaction between CO and O 2 with Group 11 Atoms on a Defect-Free MgO(001) Surface. J Phys Chem A 2018; 122:2307-2317. [PMID: 29389129 DOI: 10.1021/acs.jpca.8b00647] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this contribution, we investigate the interaction between CO and O2 with metal atoms of group 11 deposited on a defect-free magnesium oxide surface using density functional theory with periodic point charge embedding. We present the first transversal study of the adsorption and coadsorption of CO and O2 on coinage metal adatoms deposited on metal oxide surfaces from the perspective of single-atom catalysis. Various analysis tools shed light on the binding situation of the metal atoms to the substrate as well as on the situation of the two molecules on the different metal centers. Our analysis demonstrates that cooperative electronic effects enhance the stability of CO upon coadsorption with O2 for all three metal centers. Our results also explain the lack of catalytic activity of group 11 metal atoms with respect to CO oxidation under thermal conditions as a competition between OC-O2 bond activation and surface diffusion, leading to metal atom agglomeration. Additionally, it is shown how coadsorption of CO and O2 on Au/Mg(001) could pave the way to single-atom photocatalysis.
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Affiliation(s)
- Kai Töpfer
- Freie Universität Berlin , Berlin, Germany
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7
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Xu H, Xu CQ, Cheng D, Li J. Identification of activity trends for CO oxidation on supported transition-metal single-atom catalysts. Catal Sci Technol 2017. [DOI: 10.1039/c7cy00464h] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Identification of activity trends for CO oxidation on transition-metal single-atom catalysts by using Ead(CO) and Ead(O2) as descriptors.
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Affiliation(s)
- Haoxiang Xu
- Beijing Key Laboratory of Energy Environmental Catalysis
- State Key Laboratory of Organic-Inorganic Composites
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Cong-Qiao Xu
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education
- Tsinghua University
- Beijing 100084
- China
| | - Daojian Cheng
- Beijing Key Laboratory of Energy Environmental Catalysis
- State Key Laboratory of Organic-Inorganic Composites
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education
- Tsinghua University
- Beijing 100084
- China
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8
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Lykhach Y, Bruix A, Fabris S, Potin V, Matolínová I, Matolín V, Libuda J, Neyman KM. Oxide-based nanomaterials for fuel cell catalysis: the interplay between supported single Pt atoms and particles. Catal Sci Technol 2017. [DOI: 10.1039/c7cy00710h] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Nanomaterials coated with atomically dispersed platinum on ceria are structurally dynamic and show high potential for applications in fuel cells.
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Affiliation(s)
- Yaroslava Lykhach
- Lehrstuhl für Physikalische Chemie II
- Friedrich-Alexander-Universität Erlangen-Nürnberg
- 91058 Erlangen
- Germany
| | - Albert Bruix
- Department of Physics and Astronomy and Interdisciplinary Nanoscience Center
- Aarhus University
- DK-8000 Aarhus
- Denmark
| | - Stefano Fabris
- CNR-IOM DEMOCRITOS
- Istituto Officina dei Materiali
- Consiglio Nazionale delle Ricerche and SISSA
- Trieste
- Italy
| | - Valérie Potin
- Laboratoire Interdisciplinaire Carnot de Bourgogne
- UMR 6303 CNRS-Université de Bourgogne Franche-Comté
- F-21078 Dijon Cedex
- France
| | - Iva Matolínová
- Faculty of Mathematics and Physics
- Department of Surface and Plasma Science
- Charles University
- 18000 Prague
- Czech Republic
| | - Vladimír Matolín
- Faculty of Mathematics and Physics
- Department of Surface and Plasma Science
- Charles University
- 18000 Prague
- Czech Republic
| | - Jörg Libuda
- Lehrstuhl für Physikalische Chemie II
- Friedrich-Alexander-Universität Erlangen-Nürnberg
- 91058 Erlangen
- Germany
- Erlangen Catalysis Resource Center
| | - Konstantin M. Neyman
- Departament de Ciència dels Materials i Química Física and Institut de Química Teòrica i Computacional
- Universitat de Barcelona
- 08028 Barcelona
- Spain
- ICREA (Institució Catalana de Recerca i Estudis Avançats)
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9
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Zhu J, Lin S, Wen X, Fang Z, Li Y, Zhang Y, Huang X, Ning L, Ding K, Chen W. Deposition of (WO3)3 nanoclusters on the MgO(001) surface: A possible way to identify the charge states of the defect centers. J Chem Phys 2013; 138:034711. [DOI: 10.1063/1.4776219] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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10
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Pacchioni G. Electronic interactions and charge transfers of metal atoms and clusters on oxide surfaces. Phys Chem Chem Phys 2013; 15:1737-57. [DOI: 10.1039/c2cp43731g] [Citation(s) in RCA: 175] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Pacchioni G, Freund H. Electron Transfer at Oxide Surfaces. The MgO Paradigm: from Defects to Ultrathin Films. Chem Rev 2012; 113:4035-72. [DOI: 10.1021/cr3002017] [Citation(s) in RCA: 241] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Gianfranco Pacchioni
- Dipartimento di Scienza dei
Materiali, Università di Milano-Bicocca, Via R. Cozzi, 53−20125,
Milano, Italy
| | - Hajo Freund
- Fritz-Haber-Insitut
der MPG,
Department of Chemical Physics, Faradayweg 4-6, 14195 Berlin, Germany
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12
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Negreiros FR, Aprà E, Barcaro G, Sementa L, Vajda S, Fortunelli A. A first-principles theoretical approach to heterogeneous nanocatalysis. NANOSCALE 2012; 4:1208-19. [PMID: 22057595 DOI: 10.1039/c1nr11051a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A theoretical approach to heterogeneous catalysis by sub-nanometre supported metal clusters and alloys is presented and discussed. Its goal is to perform a computational sampling of the reaction paths in nanocatalysis via a global search in the phase space of structures and stoichiometry combined with filtering which takes into account the given experimental conditions (catalytically relevant temperature and reactant pressure), and corresponds to an incremental exploration of the disconnectivity diagram of the system. The approach is implemented and applied to the study of propylene partial oxidation by Ag(3) supported on MgO(100). First-principles density-functional theory calculations coupled with a Reactive Global Optimization algorithm are performed, finding that: (1) the presence of an oxide support drastically changes the potential energy landscape of the system with respect to the gas phase, favoring configurations which interact positively with the electrostatic field generated by the surface; (2) the reaction energy barriers for the various mechanisms are crucial in the competition between thermodynamically and kinetically favored reaction products; (3) a topological database of structures and saddle points is produced which has general validity and can serve for future studies or for deriving general trends; (4) the MgO(100) surface captures some major features of the effect of an oxide support and appears to be a good model of a simple oxide substrate; (5) strong cooperative effects are found in the co-adsorption of O(2) and other ligands on small metal clusters. The proposed approach appears as a viable route to advance the role of predictive computational science in the field of heterogeneous nanocatalysis.
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Affiliation(s)
- Fabio R Negreiros
- CNR-IPCF, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche, Pisa, 56124, Italy
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13
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Theoretical Modelling of Oxide-Supported Metal Nanoclusters and Nanoalloys. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/b978-0-08-096357-0.00003-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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14
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Zhang X, Xu R, Wang LJ, Hong F. Alkali metal atom adsorption on-top of the F s 0 defective center of MgO(001) surface. ACTA ACUST UNITED AC 2011. [DOI: 10.1007/s11741-011-0725-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Petrova GP, Vayssilov GN, Rösch N. Interaction of ethene and ethyne with bare and hydrogenated Ir4 clusters. A density functional study. Catal Sci Technol 2011. [DOI: 10.1039/c1cy00114k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Nasluzov VA, Ivanova-Shor EA, Shor AM, Yudanov IV, Rösch N. Simulation of heterogeneous catalysts and catalytic processes using the density functional method. KINETICS AND CATALYSIS 2010. [DOI: 10.1134/s0023158410060091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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18
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Liu Y, Wang Y, Chen G. Nucleation and mobility model of Agn clusters adsorbed on perfect and oxygen vacancy MgO surfaces. J Mol Model 2010; 17:1061-8. [DOI: 10.1007/s00894-010-0809-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Accepted: 07/12/2010] [Indexed: 11/30/2022]
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19
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König T, Simon GH, Martinez U, Giordano L, Pacchioni G, Heyde M, Freund HJ. Direct measurement of the attractive interaction forces on F0 color centers on MgO(001) by dynamic force microscopy. ACS NANO 2010; 4:2510-2514. [PMID: 20438103 DOI: 10.1021/nn100443n] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Defect sites on oxide surfaces play a dominant role in surface chemistry. The direct atomistic study of these sites is important but very difficult. We have mimicked the adsorbate-defect interaction by a dynamic force microscope tip measuring the interaction with a color center (F(0)) on the MgO(001) surface. The experimental findings, complemented by density functional theory calculations, show a highly attractive adsorbate-defect interaction and a charge transfer at a critical distance.
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Affiliation(s)
- Thomas König
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
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20
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Kuznetsov AE, Musaev DG. Does the MgO(100)-support facilitate the reaction of nitrogen and hydrogen molecules catalyzed by Zr2Pd2 clusters? A computational study. Inorg Chem 2010; 49:2557-67. [PMID: 20128599 DOI: 10.1021/ic902531p] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of the "naked" and MgO(100) supported Zr(2)Pd(2) cluster with nitrogen and four hydrogen molecules were studied at the density functional level using the periodic slab approach (VASP). It was shown that adsorption of the Zr(2)Pd(2) cluster on the MgO(100) surface does not change its gas-phase geometry and electronic structure significantly. In spite of this the N(2) coordination to the MgO(100)-supported Zr(2)Pd(2) cluster, I/MgO, is found to be almost 30 kcal/mol less favorable than for the "naked" one. The addition of the first H(2) molecule to the resulting II/MgO, that is, II/MgO + H(2) --> IV/MgO reaction, proceeds with a relatively small, 9.0 kcal/mol, barrier and is exothermic by 8.3 kcal/mol. The same reaction for the "naked" Zr(2)Pd(2) cluster requires a slightly larger barrier (10.1 kcal/mol) and is highly exothermic (by 23.3 kcal/mol). The interaction of the H(2) molecule with the intermediate IV/MgO (i.e., the second H(2) molecule addition to II/MgO) requires larger energy barrier, 23.3 kcal/mol vs 8.8 kcal/mol for the "naked" cluster, and is exothermic by 20.5 kcal/mol (vs 18.2 kcal/mol reported for the "naked" Zr(2)Pd(2) cluster). The addition of the H(2) molecule to VI/MgO and VI (i.e., the third H(2) molecule addition to II/MgO and II, respectively) requires similar barriers, 12.0 versus 16.8 kcal/mol, respectively, but is highly exothermic for the supported cluster compared to the "naked" one, 13.6 versus 0.1 kcal/mol. The addition of the fourth H(2) molecule occurs with almost twice larger barrier for the "naked" cluster compared to the adsorbed species, 30.7 versus 15.9 kcal/mol. Furthermore, this reaction step is endothermic (by 11.4 kcal/mol) for the gas-phase cluster but exothermic by 7.8 kcal/mol for the adsorbed cluster. Dissociation of the formed hydrazine molecule from the on-surface complex X/MgO and the "naked" complex X requires 19.1 and 26.3 kcal/mol, respectively. Thus, the Zr(2)Pd(2) adsorption on the MgO(100) surface facilitates its reaction with N(2) and four H(2) molecules, as well as formation of hydrazine from the hydrogen and nitrogen molecules. The reported differences in the reactivity of the "naked" and MgO adsorbed Zr(2)Pd(2) clusters were explained by analyzing the nature of the H(2) addition steps in these systems.
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Affiliation(s)
- Aleksey E Kuznetsov
- Cherry L. Emerson Center for Scientific Computation, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, USA
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21
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Petrova GP, Vayssilov GN, Rösch N. Redox behavior of small metal clusters with respect to hydrogen. The effect of the cluster charge from density functional results. Phys Chem Chem Phys 2010; 12:11015-20. [DOI: 10.1039/c004377j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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König T, Simon GH, Rust HP, Pacchioni G, Heyde M, Freund HJ. Measuring the Charge State of Point Defects on MgO/Ag(001). J Am Chem Soc 2009; 131:17544-5. [DOI: 10.1021/ja908049n] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- T. König
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany, and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy
| | - G. H. Simon
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany, and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy
| | - H.-P. Rust
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany, and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy
| | - G. Pacchioni
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany, and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy
| | - M. Heyde
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany, and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy
| | - H.-J. Freund
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany, and Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy
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23
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Ferrando R, Fortunelli A. Diffusion of adatoms and small clusters on magnesium oxide surfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:264001. [PMID: 21828449 DOI: 10.1088/0953-8984/21/26/264001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The diffusion of isolated adatoms and small clusters is reviewed for transition and noble metals adsorbed on the (001) surface of magnesium oxide. While isolated adatoms diffuse by hopping among adsorption sites, small clusters such as dimers, trimers and tetramers already display a variety of diffusion mechanisms, from cluster hopping to rotation, sliding, leapfrog, walking, concertina, flipping, twisting, rolling and rocking. Since most of the available results are computational, the review is mostly related to theoretical work. Connection to experiments is discussed where possible, mostly by dealing with the consequences that adatom and small cluster mobility may have on the growth of larger aggregates on the MgO(001) surface.
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Affiliation(s)
- Riccardo Ferrando
- Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, I-16146 Genova, Italy
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24
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Adsorption of the first row of transition metals on the perfect and defective MgO(100) surface. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.08.053] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Pacchioni G. Modeling doped and defective oxides in catalysis with density functional theory methods: room for improvements. J Chem Phys 2008; 128:182505. [PMID: 18532790 DOI: 10.1063/1.2819245] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Due to the well-known problem of the self-interaction, standard density functional theory (DFT) methods tend to produce delocalized holes and electrons in defective oxide materials even when there is ample experimental evidence of a strong localization. For late transition metal compounds or rare earth oxides, this results in the incorrect description of the electronic structure of the system (e.g., magnetic insulators are predicted to be metallic). Practical ways to correct this deficiency are based on the use of hybrid functionals or of the DFT+U approach. In this way, most of the limitations related to the self-interaction are removed, and the electronic structure is properly described. What is less clear is to what extent hybrid functionals, DFT+U approaches, or standard DFT functionals can properly describe the strength of the chemical bonds at the surface of an oxide. This is a crucial question if one is interested in the catalytic properties of oxide surfaces. Oxidation reactions often involve oxygen detachment from the surface and incorporation into an organic substrate. Oxides are doped with heteroatoms to create defects and facilitate oxygen removal from the surface, with formation of oxygen vacancies. Do standard DFT calculations provide a good binding energy of the missing oxygen despite the failure in giving the right electronic structure? Can hybrid functionals or the DFT+U approach provide a simple yet reliable way to get accurate reaction enthalpies and energy barriers? In this essay, we discuss these problems by analyzing some case histories and the relatively scarce data existing in the literature. The conclusion is that while modern electronic structure methods accurately reproduce and predict a wide range of electronic, optical, and magnetic properties of oxides, the description of the strength of chemical bonds still needs considerable improvements.
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Affiliation(s)
- Gianfranco Pacchioni
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi 53, Milan, Italy.
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26
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Pacchioni G, Sicolo S, Valentin CD, Chiesa M, Giamello E. A Route toward the Generation of Thermally Stable Au Cluster Anions Supported on the MgO Surface. J Am Chem Soc 2008; 130:8690-5. [DOI: 10.1021/ja710969t] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gianfranco Pacchioni
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi, 53 - 20125, Milano, Italy, and Dipartimento di Chimica IFM and NIS Centre of Excellence, Università di Torino, Via P. Giuria, 7 - 10125, Torino, Italy
| | - Sabrina Sicolo
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi, 53 - 20125, Milano, Italy, and Dipartimento di Chimica IFM and NIS Centre of Excellence, Università di Torino, Via P. Giuria, 7 - 10125, Torino, Italy
| | - Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi, 53 - 20125, Milano, Italy, and Dipartimento di Chimica IFM and NIS Centre of Excellence, Università di Torino, Via P. Giuria, 7 - 10125, Torino, Italy
| | - Mario Chiesa
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi, 53 - 20125, Milano, Italy, and Dipartimento di Chimica IFM and NIS Centre of Excellence, Università di Torino, Via P. Giuria, 7 - 10125, Torino, Italy
| | - Elio Giamello
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R. Cozzi, 53 - 20125, Milano, Italy, and Dipartimento di Chimica IFM and NIS Centre of Excellence, Università di Torino, Via P. Giuria, 7 - 10125, Torino, Italy
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27
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Zhu J, Farmer JA, Ruzycki N, Xu L, Campbell CT, Henkelman G. Calcium Adsorption on MgO(100): Energetics, Structure, and Role of Defects. J Am Chem Soc 2008; 130:2314-22. [DOI: 10.1021/ja077865y] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Junfa Zhu
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712-0165
| | - Jason A. Farmer
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712-0165
| | - Nancy Ruzycki
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712-0165
| | - Lijun Xu
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712-0165
| | - Charles T. Campbell
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712-0165
| | - Graeme Henkelman
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712-0165
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28
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Di Valentin C, Neyman KM, Risse T, Sterrer M, Fischbach E, Freund HJ, Nasluzov VA, Pacchioni G, Rösch N. Density-functional model cluster studies of EPR g tensors of Fs+ centers on the surface of MgO. J Chem Phys 2007; 124:044708. [PMID: 16460201 DOI: 10.1063/1.2161190] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report g tensors of surface color centers, so-called F(s) (+) centers, of MgO calculated with two density-functional approaches using accurately embedded cluster models. In line with recent UHV measurements on single-crystalline MgO film, we determined only small g-tensor anisotropies and negative shifts Deltag identical with g-g(e) for all F(s) (+) sites considered, namely, (001)-terrace, step, edge, and corner sites. The g values are very sensitive to the local structure of the defect: relaxation reverses the sign of Deltag. However, accounting for the spin-orbit interaction either self-consistently or perturbatively yields very similar results. In addition to the values of the tensor components, their direction with respect to the surface was determined. In contrast to edges, significant deviations from ideal C(2v) symmetry were found for F(s) (+) centers at steps. Recent data on single-crystalline thin films are reevaluated in the light of these results.
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Affiliation(s)
- Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università degli Studi Milano-Bicocca, 20125 Milano, Italy
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29
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Barcaro G, Aprà E, Fortunelli A. Structure of Ag Clusters Grown on Fs-Defect Sites of an MgO(1 0 0) Surface. Chemistry 2007; 13:6408-18. [PMID: 17497620 DOI: 10.1002/chem.200601796] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The structure of AgN clusters (N=1-4, 6, 8, 10), both in the gas phase and grown on the MgO(1 0 0) surface containing Fs-defects, has been investigated by a density functional basin-hopping (DF-BH) approach. In analogy with what observed in the case of gold clusters, it is found that the presence of the defect implies a double frustration and a cylindrical invariance of the metal-surface interaction, causing small Ag clusters growing around the Fs defect to be highly fluxional. Nevertheless, two different structural crossovers are found to be induced by the metal-defect interaction for the adsorbed clusters such that: 1) planar structures prevail for N<or=4 (as in the gas phase); 2) noncrystalline (fivefold symmetric) structures, which are the lowest energy ones in the gas phase for medium sized AgN clusters (N>or=7), prevail for N=6 and N=8; 3) distorted face-centered cubic (fcc) structures grown pseudomorphically on the defected surface prevail for N=10. The transition from fivefold to fcc motifs is rationalized in terms of the double-frustration effect, which increases the bond strain of the noncrystalline structures. Detrapping energies from the defect were also calculated; the lowest energy pathway corresponds to the detachment of a dimer.
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Affiliation(s)
- Giovanni Barcaro
- Molecular Modeling Laboratory, IPCF-CNR, Via G. Moruzzi 1, Pisa, 56124, Italy
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30
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A comparison between the absorption properties of the regular and F s -defected MgO (100) surface. Theor Chem Acc 2007. [DOI: 10.1007/s00214-007-0324-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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31
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Bosko SI, Moskaleva LV, Matveev AV, Rösch N. Optical Spectra of Cu, Ag, and Au Monomers and Dimers at Regular Sites and Oxygen Vacancies of the MgO(001) Surface. A Systematic Time-Dependent Density Functional Study Using Embedded Cluster Models. J Phys Chem A 2007; 111:6870-80. [PMID: 17477512 DOI: 10.1021/jp070303g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Polarization-resolved optical spectra of coinage metal monomers and dimers Mn (M=Cu, Ag, Au; n=1, 2) at ideal O2- sites of MgO(001) as well as at oxygen vacancies, Fs and Fs+, of that surface were established using a computational approach based on linear response time-dependent density functional theory. Calculations were performed for structures determined by applying a generalized-gradient density functional method to cluster models embedded in an elastic polarizable environment. This embedding scheme provides an accurate description of substrate relaxation and long-range electrostatic interaction. We compared the optical properties of adsorbed atoms and dimers with those of the corresponding gas-phase species and we systematically analyzed trends among congeners.
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Affiliation(s)
- Sergey I Bosko
- Department Chemie, Technische Universität München, 85747 Garching, Germany
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32
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Neyman KM, Inntam C, Moskaleva LV, Rösch N. Density Functional Embedded Cluster Study of Cu4, Ag4and Au4Species Interacting with Oxygen Vacancies on the MgO(001) Surface. Chemistry 2006; 13:277-86. [PMID: 16969882 DOI: 10.1002/chem.200600545] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cu(4), Ag(4), and Au(4) species adsorbed on an MgO(001) surface that exhibits neutral (F(s)) and charged (F(s) (+)) oxygen vacancies have been studied using a density functional approach and advanced embedding models. The gas-phase rhombic-planar structure of the coinage metal tetramers is only moderately affected by adsorption. In the most stable surface configuration, the plane of the tetramers is oriented perpendicular to the MgO(001) surface; one metal atom is attached to an oxygen vacancy and another one is bound to a nearby surface oxygen anion. A very similar structural motif was recently found on defect-free MgO(001), where two O(2-) ions serve as adsorption sites. Following the trend of the interactions with the regular MgO(001) surface, Au(4) and Cu(4) bind substantially stronger to F(s) and F(s) (+) sites than Ag(4). This stronger adsorption interaction at oxygen vacancies, in particular at F(s), is partly due to a notable accumulation of electron density on the adsorbates. We also examined the propensity of small supported metal species to aggregate to adsorbed di-, tri- and tetramers. Furthermore, we demonstrated that core-level ionization potentials offer the possibility for detecting experimentally supported metal tetramers and characterizing them structurally with the help of calculated data.
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Affiliation(s)
- Konstantin M Neyman
- ICREA, 08010 Barcelona and Departament de Química Física, Universitat de Barcelona, 08028 Barcelona, Spain.
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33
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Torres D, Neyman KM, Illas F. Oxygen atoms on the (111) surface of coinage metals: On the chemical state of the adsorbate. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.07.095] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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34
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Li Y, Zhang Y, Wu L, Xu Y, Chen W, Li J. A theoretical study on the dissociation of Cl2 on MgO(001) surface: Prompted by silver atoms supported on surface. Chem Phys 2006. [DOI: 10.1016/j.chemphys.2006.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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35
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Sterrer M, Fischbach E, Heyde M, Nilius N, Rust HP, Risse T, Freund HJ. Electron Paramagnetic Resonance and Scanning Tunneling Microscopy Investigations on the Formation of F+ and F0 Color Centers on the Surface of Thin MgO(001) Films. J Phys Chem B 2006; 110:8665-9. [PMID: 16640421 DOI: 10.1021/jp060546t] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The formation of surface color centers (F(S) centers) by electron bombardment of thin MgO(001) films is investigated using electron paramagnetic resonance and low-temperature scanning tunneling microscopy. At low electron doses both techniques indicate the formation of singly occupied color centers (F(S)(+)), whereas at high electron doses the doubly occupied type (F(S)(0)) is dominant. It is suggested that with increasing electron dose F(S)(+) centers are transformed into F(S)(0). Tunneling spectra of individual F(S)(0) centers reveal a large distribution of energetic positions of occupied and unoccupied states, which is caused by local variations of the coordination number of the defects and explains the broad signals usually detected with integrating spectroscopic techniques.
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Affiliation(s)
- Martin Sterrer
- Department of Chemical Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany. sterrer@ fhi-berlin.mpg.de
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36
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Di Valentin C, Neyman KM, Risse T, Sterrer M, Fischbach E, Freund HJ, Nasluzov VA, Pacchioni G, Rösch N. Density-functional model cluster studies of EPR g tensors of Fs+ centers on the surface of MgO. J Chem Phys 2006. [DOI: 10.1063/1.2161190 10.1063/1.2161190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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37
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Inntam C, Moskaleva LV, Yudanov IV, Neyman KM, Rösch N. Adsorption of Cu4, Ag4 and Au4 particles on the regular MgO(001) surface: A density functional study using embedded cluster models. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2005.10.080] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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38
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Vayssilov GN, Rösch N. Reverse hydrogen spillover in supported subnanosize clusters of the metals of groups 8 to 11. A computational model study. Phys Chem Chem Phys 2005; 7:4019-26. [DOI: 10.1039/b511842e] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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