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Filardi LR, Vila FD, Hong J, Hoffman AS, Perez-Aguilar JE, Bare SR, Runnebaum RC, Kronawitter CX. Impact of Local Structure in Supported CaO Catalysts for Soft-Oxidant-Assisted Methane Coupling Assessed through Ca K-Edge X-ray Absorption Spectroscopy. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2024; 128:1165-1176. [PMID: 38293693 PMCID: PMC10823472 DOI: 10.1021/acs.jpcc.3c06527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 02/01/2024]
Abstract
Soft-oxidant-assisted methane coupling has emerged as a promising pathway to upgrade methane from natural gas sources to high-value commodity chemicals, such as ethylene, at selectivities higher than those associated with oxidative (O2) methane coupling (OCM). To date, few studies have reported investigations into the electronic structure and the microscopic physical structure of catalytic active sites present in the binary metal oxide catalyst systems that are known to be effective for this reaction. Correlating the catalyst activity to specific active site structures and electronic properties is an essential aspect of catalyst design. Here, we used X-ray absorption spectroscopy at the Ca K-edge to ascertain the most probable local environment of Ca in the ZnO-supported Ca oxide catalysts. These catalysts are shown here to be active for N2O-assisted methane coupling (N2O-OCM) and have previously been reported to be active for CO2-assisted methane coupling (CO2-OCM). X-ray absorption near edge structure features at multiple Ca loadings are interpreted through simulated spectra derived from ab initio full multiple scattering calculations. These simulations included consideration of CaO structures organized in multiple spatial arrangements-linear, planar, and cubic-with separate analyses of Ca atoms in the surfaces and bulk of the three-dimensional structures. The morphology of the oxide clusters was found to influence the various regions of the X-ray absorption spectrum differently. Experiment and theory show that for low-Ca-loading catalysts (≤1 mol %), which contain sites particularly active for methane coupling, Ca primarily exists in an oxidized state that is consistent with the coordination environment of Ca ions in one- and two-dimensional clusters. In addition to their unique nanoscale structures, the spectra also indicate that these clusters have varying degrees of undercoordinated surface Ca atoms that could further influence their catalytic activities. The local Ca structure was correlated to methane coupling activity from N2O-OCM and previously reported CO2-OCM reactor studies. This study provides a unique perspective on the relationship between the catalyst physical and electronic structure and active sites for soft-oxidant-assisted methane coupling, which can be used to inform future catalyst development.
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Affiliation(s)
- Leah R. Filardi
- Department
of Chemical Engineering, University of California,
Davis, Davis, California 95616, United States
| | - Fernando D. Vila
- Department
of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiyun Hong
- SSRL,
SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Adam S. Hoffman
- SSRL,
SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | | | - Simon R. Bare
- SSRL,
SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Ron C. Runnebaum
- Department
of Chemical Engineering, University of California,
Davis, Davis, California 95616, United States
- Department
of Viticulture & Enology, University
of California, Davis, Davis, California 95616, United States
| | - Coleman X. Kronawitter
- Department
of Chemical Engineering, University of California,
Davis, Davis, California 95616, United States
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2
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Li Z, Shen X, Zhao Z. Structures, stability, electronic and magnetic properties of the TMFe2O4@Cn (TM = Mn, Fe, Co and Ni, n = 50, 60, 70) clusters. Theor Chem Acc 2021. [DOI: 10.1007/s00214-021-02809-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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3
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Zhao Z, Li Z. First-principle calculations on the structures and electronic properties of the CO-adsorbed (SnO2)2 clusters. Struct Chem 2020. [DOI: 10.1007/s11224-020-01554-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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Escatllar AM, Lazaukas T, Woodley SM, Bromley ST. Structure and Properties of Nanosilicates with Olivine (Mg 2SiO 4) N and Pyroxene (MgSiO 3) N Compositions. ACS EARTH & SPACE CHEMISTRY 2019; 3:2390-2403. [PMID: 32055761 PMCID: PMC7009040 DOI: 10.1021/acsearthspacechem.9b00139] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/25/2019] [Accepted: 07/18/2019] [Indexed: 05/26/2023]
Abstract
Magnesium-rich silicates are ubiquitous both terrestrially and astronomically, where they are often present as small particles. Nanosized Mg-rich silicate particles are likely to be particularly important for understanding the formation, processing, and properties of cosmic dust grains. Although astronomical observations and laboratory studies have revealed much about such silicate dust, our knowledge of this hugely important class of nanosolids largely rests on top-down comparisons with the properties of bulk silicates. Herein, we provide a foundational bottom-up study of the structure and properties of Mg-rich nanosilicates based on carefully procured atomistic models. Specifically, we employ state-of-the-art global optimization methods to search for the most stable structures of silicate nanoclusters with olivine (Mg2SiO4) N and pyroxene (MgSiO3) N compositions with N = 1-10. To ensure the reliability of our searches, we develop a new interatomic potential that has been especially tuned for nanosilicates. Subsequently, we refine these searches and calculate a range of physicochemical properties of the most stable nanoclusters using accurate density functional theory based electronic structure calculations. We report a detailed analysis of structural and energy properties, charge distributions, and infrared vibrational spectra, where in all cases we compare our finding for nanosilicates with those of the corresponding bulk silicate crystals. For most properties considered, we find large differences with respect to the bulk limit, underlining the limitations of a top-down approach for describing these species. Overall, our work provides a new platform for an accurate and detailed understanding of nanoscale silicates.
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Affiliation(s)
- Antoni Macià Escatllar
- Departament
de Ciència de Materials i Química Física &
Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, E-08028 Barcelona, Spain
| | - Tomas Lazaukas
- Department
of Chemistry, University College, London WC1H 0AJ, U.K.
| | - Scott M. Woodley
- Department
of Chemistry, University College, London WC1H 0AJ, U.K.
| | - Stefan T. Bromley
- Departament
de Ciència de Materials i Química Física &
Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, E-08028 Barcelona, Spain
- Institució
Catalana de Recerca i Estudis Avançats (ICREA), E-08010 Barcelona, Spain
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Xiao Y, Lei H, Zhang H, Wang G, Wang Q, Jin W. Structural evolution of calcia during calcium deoxidation in Fe-O-Ca melt. Phys Chem Chem Phys 2019; 21:13847-13855. [PMID: 31211308 DOI: 10.1039/c9cp02212k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The crystallization process of CaO in iron melt begins with nucleation, which determines the structure and size of the CaO inclusions; thus, it is important to investigate the mechanism of inclusion modification by calcium treatment. In this study, a two-step nucleation method was used to investigate the behavior during the early stages of CaO inclusion crystallization. The first principles method was applied to calculate the structures and properties of CaO crystals and CaO clusters. Then, the nucleation mechanism of CaO in the Fe-O-Ca melt has been discussed. The numerical results show that CaO clusters with cubic structures and appropriate variations are the lowest energy structures and are more stable than other isomers. The stability of the cubic (CaO)n clusters increases with the increase in size and gradually approaches that of the CaO crystal. CaO clusters can form spontaneously in the Fe-O-Ca melt, while the transformation reaction of the CaO clusters in the Fe-O-Ca melt deeply depends on the supersaturation ratio of [Ca] and [O]. CaO clusters may remain as suspended CaO inclusions in the iron melt for a long time, and these suspensions of CaO clusters are the source of excess oxygen in the iron melt.
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Affiliation(s)
- Yuanyou Xiao
- Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang, Liaoning Province 110819, P. R. China. and School of Metallurgy, Northeastern University, Shenyang, Liaoning Province 110819, P. R. China and Key Laboratory of Chemical Metallurgy Engineering Liaoning Province, University of Science and Technology Liaoning, Anshan, Liaoning Province 114051, P. R. China.
| | - Hong Lei
- Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang, Liaoning Province 110819, P. R. China. and School of Metallurgy, Northeastern University, Shenyang, Liaoning Province 110819, P. R. China
| | - Hongwei Zhang
- Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang, Liaoning Province 110819, P. R. China. and School of Metallurgy, Northeastern University, Shenyang, Liaoning Province 110819, P. R. China
| | - Guocheng Wang
- Key Laboratory of Chemical Metallurgy Engineering Liaoning Province, University of Science and Technology Liaoning, Anshan, Liaoning Province 114051, P. R. China.
| | - Qi Wang
- Key Laboratory of Chemical Metallurgy Engineering Liaoning Province, University of Science and Technology Liaoning, Anshan, Liaoning Province 114051, P. R. China.
| | - Wei Jin
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu Province 214122, P. R. China
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Zobeydi R, Nazari P, Rahman Setayesh S. Theoretical study of the thermodynamic parameters of (CaO)n nanoclusters with n = 2–16 in the gas and solution phases: proton affinity, molecular basicity, and pKb values. Struct Chem 2019. [DOI: 10.1007/s11224-019-01318-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Li Z, Zhao Z. The reaction mechanism of a M (M = Mn, Fe, Co and Ni) atom inserted into a Fe8O12 cage. RESEARCH ON CHEMICAL INTERMEDIATES 2018. [DOI: 10.1007/s11164-018-3646-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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8
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Masuzaki D, Takehashi Y, Mafuné F. Stability and Effect of Hydration on Calcium Oxide Cluster Ions, CanOm+, in the Gas Phase. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2018. [DOI: 10.1246/bcsj.20180149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Daigo Masuzaki
- Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan
| | - Yuma Takehashi
- Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan
| | - Fumitaka Mafuné
- Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan
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Density functional theory study on geometries, stability and electronic structures of CamMgn-mOn (m = 1–2, n = 2–10) clusters. COMPUT THEOR CHEM 2016. [DOI: 10.1016/j.comptc.2016.09.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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10
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Srivastava AK, Misra N. Ab initioinvestigations on planar (MgO)nclusters (n = 1–5) and their hydrogen adsorption behaviour. MOLECULAR SIMULATION 2015. [DOI: 10.1080/08927022.2015.1032278] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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11
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Cheng H, Cheng L. Secondary bonding networks in small (HgS)n clusters: A theoretical investigation. COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.02.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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12
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Structures and Stabilities of Alkaline Earth Metal Oxide Nanoclusters: A DFT Study. ACTA ACUST UNITED AC 2013. [DOI: 10.1155/2013/720794] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The stability orders of a number of alkaline earth oxide cluster isomers (MO)n, M = Mg, Ca, Sr, Ba and 1≤n≥6 have been determined by means of density functional theory studies using the LDA-PWC functional. Among the candidate structures, the hexagonal-ring-based isomers and the slab shapes are found to display similar stabilities. Stacks of hexagonal (MO)3 rings are found to be the slightly preferred growth strategy among the (MgO)6, isomers. In contrast, the slab structures are slightly preferred for the other alkaline metal oxide (MO)6 clusters. An explanation based on packing and aromaticity arguments has been proposed. This study may have important implications for modeling and understanding the initial growth patterns of small nanostructures of alkaline earth metals.
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13
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Ren L, Cheng L, Feng Y, Wang X. Geometric and electronic structures of (BeO)N (N = 2–12, 16, 20, and 24): Rings, double rings, and cages. J Chem Phys 2012; 137:014309. [DOI: 10.1063/1.4731808] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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14
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Lowest-energy structures of (MgO)n (n=2–7) clusters from a topological method and first-principles calculations. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2011.11.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Cao B, Starace AK, Judd OH, Bhattacharyya I, Jarrold MF, López JM, Aguado A. Activation of Dinitrogen by Solid and Liquid Aluminum Nanoclusters: A Combined Experimental and Theoretical Study. J Am Chem Soc 2010; 132:12906-18. [DOI: 10.1021/ja103356r] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Baopeng Cao
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
| | - Anne K. Starace
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
| | - Oscar H. Judd
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
| | - Indrani Bhattacharyya
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
| | - Martin F. Jarrold
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
| | - José M. López
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
| | - Andrés Aguado
- Chemistry Department, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, and Departamento de Física Teórica, Universidad de Valladolid, Valladolid 47011, Spain
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16
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Zhang Y, Chen HS, Liu BX, Zhang CR, Li XF, Wang YC. Melting of (MgO)n (n=18, 21, and 24) clusters simulated by molecular dynamics. J Chem Phys 2010; 132:194304. [DOI: 10.1063/1.3425844] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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17
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Carrasco J, Illas F, Bromley ST. Ultralow-density nanocage-based metal-oxide polymorphs. PHYSICAL REVIEW LETTERS 2007; 99:235502. [PMID: 18233380 DOI: 10.1103/physrevlett.99.235502] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Indexed: 05/25/2023]
Abstract
For two important metal oxides (MO, M=Mg, Zn) we predict, via accurate electronic structure calculations, that new low-density nanoporous crystalline phases may be accessible via the coalescence of nanocluster building blocks. Specifically, we consider the assembly of cagelike (MO)_{12} clusters exhibiting particularly high gas phase stability, leading to new polymorphs with energetic stabilities rivaling (and sometimes higher) than those of known MO polymorphs.
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Affiliation(s)
- Javier Carrasco
- Dept. Química Física & IQTCUB, Universitat de Barcelona, 08028 Barcelona, Spain
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18
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Srnec M, Zahradník R. Small Group IIa–VIa Clusters and Related Systems: A Theoretical Study of Physical Properties, Reactivity, and Electronic Spectra. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200600816] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Investigating the role of cationic vacancy on the MgO (001) defect surface: Embedded cluster models study. Chem Phys 2005. [DOI: 10.1016/j.chemphys.2005.04.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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20
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Goniakowski J, Noguera C, Giordano L. Using polarity for engineering oxide nanostructures: structural phase diagram in free and supported MgO(111) ultrathin films. PHYSICAL REVIEW LETTERS 2004; 93:215702. [PMID: 15601031 DOI: 10.1103/physrevlett.93.215702] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2004] [Indexed: 05/04/2023]
Abstract
Using an ab initio total energy approach, we study the stability of free and Ag(111)-supported MgO(111) ultrathin films. We unravel a novel microscopic mechanism of stabilization of polar oxide orientations, based on a strong modification of the MgO structural phase diagram with respect to the bulk material. We predict that, at low thickness, films which are either unsupported or deposited on Ag(111) display a graphitelike Bk structure rather than the expected rocksalt one. Our results provide a consistent interpretation of recent experimental findings, exemplify the efficiency of this novel stabilization mechanism, and suggest new methods to engineer oxide nanostructures.
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Affiliation(s)
- Jacek Goniakowski
- Groupe de Physique des Solides, UMR 7588 CNRS, Universités Paris 6-Paris 7, Campus de Boucicaut, 140 rue de Lourmel, 75015 Paris, France.
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Xu YJ, Li JQ, Zhang YF, Chen WK. The adsorption and dissociation of Cl2 on the MgO (001) surface with vacancies: Embedded cluster model study. J Chem Phys 2004; 120:8753-60. [PMID: 15267807 DOI: 10.1063/1.1697375] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The adsorption of Cl(2) at a low-coordinated oxygen site (edge or corner site) and vacancy site (terrace, edge, corner F, F(+), or F(2+) center) has been studied by the density functional method, in conjunction with the embedded cluster models. First, we have studied the adsorption of Cl(2) at the edge and corner oxygen sites and the results show that Cl(2), energetically, is inclined to adsorb at the corner oxygen site. Moreover, similar to the most advantageous adsorption mode for Cl(2) on the MgO (001) perfect surface, the most favorable adsorption occurs when Cl(2) approaches the corner oxygen site along the normal direction. A small amount of electrons are transferred from the substrate to the antibonding orbital of the adsorbate, leading to the Cl-Cl bond strength weakened a little. Regarding Cl(2) adsorption at the oxygen vacancy site (F, F(+), or F(2+) center), both large adsorption energies and rather much elongation of the Cl-Cl bond length have been obtained, in particular at the corner oxygen vacancy site, with concurrently large amounts of electrons transferred from the substrate to the antibonding orbital of Cl(2). It suggests, at the oxygen vacancy site, that Cl(2) prefers to dissociate into Cl subspecies. And the potential energy surface indicates that the dissociation process of molecular Cl(2) to atomic Cl is virtually barrierless.
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Affiliation(s)
- Yi-Jun Xu
- Department of Chemistry, Fuzhou University, Fuzhou, 350002,
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22
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Chen G, Liu ZF, Gong XG. Ab initio study on structural and electronic properties of BanOm clusters. J Chem Phys 2004; 120:8020-4. [PMID: 15267720 DOI: 10.1063/1.1691785] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Density-functional calculation within local density approximation, shows that the electronic property of a barium oxide cluster is strongly correlated with its equilibrium structure. The ground-state structures of BanOm (4 < or = n < or = 9,m < or = n) clusters can be classified into four categories: (a) compact, (b) dangling state, (c) F-center, and (d) stoichiometric. The compact cluster is metallic, almost no energy gap exists between the highest occupied and the lowest unoccupied molecular orbitals. The energy gap for the dangling state cluster is larger than that for the F-center cluster, while the stoichiometric cluster has the largest energy gap.
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Affiliation(s)
- G Chen
- Institute of Solid State Physics, Chinese Academy of Sciences, 230031-Hefei, P. R. China
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23
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Aguado A, Madden PA. Oxide potentials from ab initio molecular dynamics: An assessment of their transferability. J Chem Phys 2003. [DOI: 10.1063/1.1556073] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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Aguado A, Bernasconi L, Madden PA. Interionic potentials from ab initio molecular dynamics: The alkaline earth oxides CaO, SrO, and BaO. J Chem Phys 2003. [DOI: 10.1063/1.1556074] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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25
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Johnston RL, Roberts C. Genetic Algorithms for the Geometry Optimization of Clusters and Nanoparticles. SOFT COMPUTING APPROACHES IN CHEMISTRY 2003. [DOI: 10.1007/978-3-540-36213-5_7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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27
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Aguado A, Madden PA. Molecular dynamics simulations of the liquid–vapor interface of a molten salt. III. Size asymmetry effects and binary mixtures. J Chem Phys 2002. [DOI: 10.1063/1.1508773] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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28
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Vyboishchikov SF, Sauer J. (V2O5)n Gas-Phase Clusters (n = 1−12) Compared to V2O5 Crystal: DFT Calculations. J Phys Chem A 2001. [DOI: 10.1021/jp012294w] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sergei F. Vyboishchikov
- Humboldt-Universität zu Berlin, Institut für Chemie, Arbeitsgruppe Quantenchemie, Jägerstr.10-11, D-10117 Berlin, Germany
| | - Joachim Sauer
- Humboldt-Universität zu Berlin, Institut für Chemie, Arbeitsgruppe Quantenchemie, Jägerstr.10-11, D-10117 Berlin, Germany
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29
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Aguado A. Anab initiostudy of the lattice distortions induced by nonisovalent Ge2+, Sn2+, and Pb2+ substitutional impurities in crystalline NaCl. J Chem Phys 2001. [DOI: 10.1063/1.1352729] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Aguado A. An ab Initio Study of the Structures and Relative Stabilities of Doubly Charged [(NaCl)m(Na)2]2+ Cluster Ions. J Phys Chem B 2001. [DOI: 10.1021/jp004222v] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrés Aguado
- Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, U.K
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31
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Aguado A. Ga+, In+, and Tl+ impurities in alkali halide crystals: Distortion trends. J Chem Phys 2000. [DOI: 10.1063/1.1317520] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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