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Li HF, Wang HQ, Zhang JM, Qin LX, Zheng H, Zhang YH. Investigation of Structures, Stabilities, and Electronic and Magnetic Properties of Niobium Carbon Clusters Nb 7C n (n = 1-7). Molecules 2024; 29:1692. [PMID: 38675512 PMCID: PMC11051814 DOI: 10.3390/molecules29081692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/03/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
The geometrical structures, relative stabilities, and electronic and magnetic properties of niobium carbon clusters, Nb7Cn (n = 1-7), are investigated in this study. Density functional theory (DFT) calculations, coupled with the Saunders Kick global search, are conducted to explore the structural properties of Nb7Cn (n = 1-7). The results regarding the average binding energy, second-order difference energy, dissociation energy, HOMO-LUMO gap, and chemical hardness highlight the robust stability of Nb7C3. Analysis of the density of states suggests that the molecular orbitals of Nb7Cn primarily consist of orbitals from the transition metal Nb, with minimal involvement of C atoms. Spin density and natural population analysis reveal that the total magnetic moment of Nb7Cn predominantly resides on the Nb atoms. The contribution of Nb atoms to the total magnetic moment stems mainly from the 4d orbital, followed by the 5p, 5s, and 6s orbitals.
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Affiliation(s)
- Hui-Fang Li
- College of Engineering, Huaqiao University, Quanzhou 362021, China
| | - Huai-Qian Wang
- College of Engineering, Huaqiao University, Quanzhou 362021, China
- College of Information Science and Engineering, Huaqiao University, Xiamen 361021, China
| | - Jia-Ming Zhang
- College of Information Science and Engineering, Huaqiao University, Xiamen 361021, China
| | - Lan-Xin Qin
- College of Engineering, Huaqiao University, Quanzhou 362021, China
| | - Hao Zheng
- College of Information Science and Engineering, Huaqiao University, Xiamen 361021, China
| | - Yong-Hang Zhang
- College of Information Science and Engineering, Huaqiao University, Xiamen 361021, China
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Geng L, Sengupta T, Li X, Cui C, Lin S, Xu XL, Reber AC, Khanna SN, Zheng WJ, Luo Z. Unusually High-Spin Fe 12C 12- Metallo-Carbohedrene Clusters. J Am Chem Soc 2023. [PMID: 38041728 DOI: 10.1021/jacs.3c09690] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
Ferromagnets constructed from nanometals of atomic precision are important for innovative advances in information storage, energy conversion, and spintronic microdevices. Considerable success has been achieved in designing molecular magnets, which, however, are challenging in preparation and may suffer from drawbacks on the incompatibility of high stability and strong ferromagnetism. Utilizing a state-of-the-art self-developed mass spectrometer and a homemade laser vaporization source, we have achieved a highly efficient preparation of pure iron clusters, and here, we report the finding of a strongly ferromagnetic metal-carbon cluster, Fe12C12-, simply by reacting the Fen- clusters with acetylene in proper conditions. The unique stability of this ferromagnetic Fe12C12- cluster is rooted in a plumb-bob structure pertaining to Jahn-Teller distortion. We classify Fe12C12- as a new member of metallo-carbohedrenes and elucidate its structural stability mechanism as well as its soft-landing deposition and magnetization measurements, providing promise for the exploration of potential applications.
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Affiliation(s)
- Lijun Geng
- Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Turbasu Sengupta
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000, United States
| | - Xilong Li
- State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Chaonan Cui
- Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Shiquan Lin
- Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Xi-Ling Xu
- State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Arthur C Reber
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000, United States
| | - Shiv N Khanna
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000, United States
| | - Wei-Jun Zheng
- State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- School of Chemical Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhixun Luo
- Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- School of Chemical Science, University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Gan W, Huang B, Cui C, Hansen K, Luo Z. Weak Interactions Initiate C-H and C-C Bond Dissociation of Ethane on Nb n + Clusters. Chemphyschem 2023; 24:e202200530. [PMID: 36807961 DOI: 10.1002/cphc.202200530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/23/2023]
Abstract
The conversion of ethane into value-added chemicals under ambient conditions has attracted much attention but the mechanisms remain not fully understood. Here we report a study on the reaction of ethane with thermalized Nbn + clusters based on a multiple-ion laminar flow tube reactor combined with a triple quadrupole mass spectrometer (MIFT-TQMS). It is found that ethane reacts with Nbn + clusters to form both products of dehydrogenation and methane-removal (odd-carbon products). Combined with density functional theory (DFT) calculations, we studied the reaction mechanisms of the C-C bond activation and C-H bond cleavage on the Nbn + clusters. It is unveiled that hydrogen atom transfer (HAT) initiates the reaction process, giving rise to the formation of Nb-C bonds and an elongated C-C distance in the HNbn + CH2 CH3 motif. Subsequent reactions allow for C-C bond activation and a competitive HAT process which is associated with CH4 removal or H2 release, resulting in the production of the observed carbides.
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Affiliation(s)
- Wen Gan
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of, Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Benben Huang
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of, Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chaonan Cui
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of, Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Klavs Hansen
- Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, 92 Weijin Road, Tianjin, 300072, China
| | - Zhixun Luo
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of, Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
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Gan W, Huang B, Yang M, Geng L, Luo Z, Hansen K. The reactivity of Nb n+ clusters with acetylene and ethylene to produce a cubic aromatic metal carbide Nb 4C 4+. NEW J CHEM 2021. [DOI: 10.1039/d1nj04750g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The reactions of niobium cationic clusters with acetylene and ethylene under sufficient gas collision conditions give rise to dominant dehydrogenation and produce a main metal carbide Nb4C4+ which is associated with cubic aromaticity.
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Affiliation(s)
- Wen Gan
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Benben Huang
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengzhou Yang
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lijun Geng
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhixun Luo
- Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Klavs Hansen
- Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
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Ai LY, Zhao HY, Ma HM, Wang J, Liu Y. Ti 12C 68: A stable T h -symmetry hollow cage. Sci Rep 2018; 8:4167. [PMID: 29520030 PMCID: PMC5843587 DOI: 10.1038/s41598-018-22381-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 02/22/2018] [Indexed: 12/02/2022] Open
Abstract
A stable T h -symmetry Ti12C68 cage was systemically investigated using density functional theory. The structure of Ti12C68 is a hollow cage with twelve TiC13 subunit of three pentagons and one hexagon. The calculated frequencies are in the range 95.1 cm-1-1423.9 cm-1. There are no imaginary frequencies, showing its kinetic stability. Ab initio molecular dynamics simulations demonstrate that the topological structure of cage-like Ti12C68 cluster was well maintained when the effective temperature is up to 1139 K. The natural bond orbitals analysis shows that the d orbit of Ti atoms form four σ bonds with the neighboring four carbon atoms in each TiC13 subunit playing an important role in the cluster stability. The molecular frontier orbitals analysis indicates that Ti12C68 cage has a narrow HOMO-LUMO gap with metal-like property. It would be expected to enrich the species of hollow metal carbide clusters.
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Affiliation(s)
- Ling-Yan Ai
- Department of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
- North China University of Science and Technology, Tangshan, 063000, China
| | - Hui-Yan Zhao
- Department of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Hong-Man Ma
- Department of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Jing Wang
- Department of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Ying Liu
- Department of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Shijiazhuang, 050024, Hebei, China.
- National Key Laboratory for Materials Simulation and Design, Beijing, 100083, China.
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Chernyy V, Logemann R, Bakker JM, Kirilyuk A. Determination of the geometric structure of neutral niobium carbide clusters via infrared spectroscopy. J Chem Phys 2016; 145:164305. [DOI: 10.1063/1.4965917] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- V. Chernyy
- Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - R. Logemann
- Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - J. M. Bakker
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525 ED Nijmegen, The Netherlands
| | - A. Kirilyuk
- Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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Dryza V, Alvino JF, Metha GF. Onset of Carbon−Carbon Bonding in Ta5Cy(y= 0−6) Clusters: A Threshold Photoionization and Density Functional Theory Study. J Phys Chem A 2010; 114:4080-5. [PMID: 20192196 DOI: 10.1021/jp100118r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Viktoras Dryza
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
| | - Jason F. Alvino
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
| | - Gregory F. Metha
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
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10
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Clayborne PA, Jones CE, Gupta U, Melko JJ, Khanna SN, Castleman AW. Structural evolution of triniobium carbide clusters: evidence of large Cn chains (n = 3-4) in Nb3Cn- (n = 5-10) clusters. J Phys Chem A 2010; 114:1290-7. [PMID: 19673506 DOI: 10.1021/jp905022p] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
First-principle density functional calculations and photoelectron spectroscopy experiments show that triniobium carbide clusters exist in multiple motifs. The Nb(3)C(n)(-) (n = 5-10) series have isomers surrounding a triangular Nb(3) base while incorporating Nb-C bonding. We provide evidence of not only C(2) carbon chains but also stable isomers with previously unidentified C(3) and C(4) carbon chains in triniobium carbide clusters.
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Affiliation(s)
- Peneé A Clayborne
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000, USA
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11
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Dryza V, Metha GF. Threshold photoionization and density functional theory studies of bimetallic-carbide nanocrystals and fragments: Ta3ZrC(y) (y = 0-4). J Chem Phys 2009; 130:244301. [PMID: 19566147 DOI: 10.1063/1.3154384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Gas-phase bimetallic tantalum-zirconium-carbide clusters are generated using a constructed double ablation cluster source. The Ta(3)ZrC(y) (y = 0-4) clusters are examined by photoionization efficiency spectroscopy to extract experimental ionization energies (IEs). The IE trend for the Ta(3)ZrC(y) cluster series is reasonably similar to that of the Ta(4)C(y) cluster series [V. Dryza et al., J. Phys. Chem. A 109, 11180 (2005)], although the IE reductions upon carbon addition are greater for the former. Complementary density functional theory calculations are performed for the various isomers constructed by attaching carbon atoms to the different faces of the tetrahedral Ta(3)Zr cluster. The good agreement between the experimental IE trend and that calculated for these isomers support a 2x2x2 face centered cubic nanocrystal structure for Ta(4)ZrC(4) and nanocrystal fragment structures for the smaller clusters.
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Affiliation(s)
- V Dryza
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
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12
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Fukushima N, Miyajima K, Mafuné F. Ionization Energies of Niobium Carbide Clusters NbnCm (n = 3−10, m = 0−7). J Phys Chem A 2009; 113:2309-15. [DOI: 10.1021/jp809915c] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Naoya Fukushima
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Ken Miyajima
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Fumitaka Mafuné
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
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13
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Dryza V, Gascooke JR, Buntine MA, Metha GF. Onset of carbon–carbon bonding in the Nb5Cy(y = 0–6) clusters: a threshold photo-ionisation and density functional theory study. Phys Chem Chem Phys 2009; 11:1060-8. [DOI: 10.1039/b813359j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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14
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Ticknor BW, Bandyopadhyay B, Duncan MA. Photodissociation of Noble Metal-Doped Carbon Clusters. J Phys Chem A 2008; 112:12355-66. [DOI: 10.1021/jp807867r] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- B. W. Ticknor
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556
| | - B. Bandyopadhyay
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556
| | - M. A. Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556
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15
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Miyajima K, Fukushima N, Mafuné F. Reactivity of Niobium−Carbon Cluster Ions with Hydrogen Molecules in Relation to Formation Mechanism of Met−Car Cluster Ions. J Phys Chem A 2008; 112:5774-6. [PMID: 18537226 DOI: 10.1021/jp803247h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ken Miyajima
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Naoya Fukushima
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Fumitaka Mafuné
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
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16
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Dryza V, Addicoat MA, Gascooke JR, Buntine MA, Metha GF. Threshold Photoionization and Density Functional Theory Studies of the Niobium Carbide Clusters Nb3Cn (n = 1−4) and Nb4Cn (n = 1−6). J Phys Chem A 2008; 112:5582-92. [DOI: 10.1021/jp800691s] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Viktoras Dryza
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
| | - Matthew A. Addicoat
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
| | - Jason R. Gascooke
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
| | - Mark. A. Buntine
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
| | - Gregory F. Metha
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
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17
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Knappenberger KL, Clayborne PA, Reveles JU, Sobhy MA, Jones CE, Gupta UU, Khanna SN, Iordanov I, Sofo J, Castleman AW. Anion photoelectron spectroscopy and density functional investigation of diniobium-carbon clusters. ACS NANO 2007; 1:319-326. [PMID: 19206683 DOI: 10.1021/nn700167c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Experimental photoelectron and computational results show diniobium-carbon (Nb(2)C(n)) clusters to coexist in multiple structural isomers: three-dimensional geometries, planar rings, and linear chains. Three-dimensional clusters having up to five carbons are formed preferentially with Nb-Nb bonding, whereas only Nb-C bonding is observed experimentally at six carbons. Clusters consisting of an odd number of atoms are also observed with linear geometries. The larger binary clusters (n > or = 7) display properties similar to those of pure carbon clusters. We provide evidence for niobium substitution of carbon atoms.
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Affiliation(s)
- K L Knappenberger
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
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Knappenberger KL, Jones CE, Sobhy MA, Iordanov I, Sofo J, Castleman AW. Anion Photoelectron Spectroscopy and Density Functional Investigation of Vanadium Carbide Clusters. J Phys Chem A 2006; 110:12814-21. [PMID: 17125295 DOI: 10.1021/jp065273g] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The influence of source conditions on vanadium-carbon cluster formation in a methane-vanadium plasma is explored and analyzed by photoelectron spectroscopy, revealing that the metal-carbon ratio has substantial influence over the cluster products. Experiments that employ large methane content produce carbon-rich mono- and divanadium carbides. The carbon-rich clusters show a preference for the formation of cyclic neutral and linear ionic structures. When the methane concentration is decreased, VmCn clusters are formed with m = 1-4 and n = 2-8. The photoelectron spectra of clusters formed under these conditions are indicative of a three-dimensional network. We have measured a significantly lower vertical electron affinity for the VC2, V2C3, and V4C6 clusters compared with proximate species. Interestingly, the VC2 species is a proposed building block of the M8C12 Met-Car cluster, and the 2,3 and 4,6 clusters correspond to the 1/4 and 1/2 Met-Car cages, respectively. This correlation is taken as evidence of their importance in the formation of the larger Met-Car species. These results are supported by density functional theory (DFT) calculations carried out at the PBE/GGA level.
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Affiliation(s)
- K L Knappenberger
- Departments of Chemistry and Physics, The Pennsylvania State University, University Park, PA 16802, USA
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Martinez JI, Castro A, Rubio A, Alonso JA. Photoabsorption spectra of Ti8C12 metallocarbohedrynes: Theoretical spectroscopy within time-dependent density functional theory. J Chem Phys 2006; 125:074311. [PMID: 16942343 DOI: 10.1063/1.2263732] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The photoabsorption spectra of several of the most stable isomers of the Ti8C12 metallocarbohedryne are calculated using time-dependent density functional theory. Several ground-state magnitudes have been also calculated, such as cohesive energies, electronic gaps between the highest occupied and lowest unoccupied molecular orbitals, and static polarizabilities. Since significant differences are found among the photoabsorption spectra of the different isomers in the low energy region (0-5 eV), we propose the comparison of experimental and the calculated absorption spectra as a tool to elucidate the isomers that appear to form in the experiments. Between 10 and 13 eV all the spectra show a region of high absorption that we identify as due to collective electronic excitations. The existence of this prominent feature explains the occurrence of delayed ionization and delayed ion emission phenomena observed in previous experiments.
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Affiliation(s)
- J I Martinez
- Departamento de Fisica Teórica, Atómica y Optica, Universidad de Valladolid, 47001 Valladolid, Spain.
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Dryza V, Addicoat MA, Gascooke JR, Buntine MA, Metha GF. Ionization Potentials of Tantalum−Carbide Clusters: An Experimental and Density Functional Theory Study. J Phys Chem A 2005; 109:11180-90. [PMID: 16331901 DOI: 10.1021/jp054410r] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have used photoionization efficiency spectroscopy to determine the ionization potentials (IP) of the tantalum-carbide clusters, Ta3Cn (n = 1-3) and Ta4Cn (n = 1-4). The ionization potentials follow an overall reduction as the number of carbon atoms increases; however, the trend is not steady as expected from a simple electrostatic argument. Instead, an oscillatory behavior is observed such that clusters with an odd number of carbon atoms have higher IPs and clusters with an even number of carbon atoms have lower IPs, with the Ta4C4 cluster exhibiting the lowest IP. Excellent agreement is found with relative IPs calculated using density functional theory for the lowest energy structures, which are consistent with the development of a 2 x 2 x 2 face-centered nanocrystal. This work shows that IPs may be used as a reliable validation for the geometries of metal-carbide clusters calculated by theory. The variation in IP can also be interpreted qualitatively with application of a simple model based upon isolobal frontier orbitals.
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Affiliation(s)
- Viktoras Dryza
- Department of Chemistry, The University of Adelaide, South Australia 5005, Australia
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Martínez J, Castro A, Rubio A, Poblet J, Alonso J. Calculation of the optical spectrum of the Ti8C12 and V8C12 Met-Cars. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.09.058] [Citation(s) in RCA: 10] [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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Stairs JR, Peppernick SJ, Davis KM, Castleman AW. Time-Resolved Fluence Studies and Delayed Ionization of the Niobium-Carbon Cluster System. Isr J Chem 2004. [DOI: 10.1560/xh55-0a98-b2c4-grql] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Bruce MI, Low PJ. Transition Metal Complexes Containing All-Carbon Ligands. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2004. [DOI: 10.1016/s0065-3055(03)50004-1] [Citation(s) in RCA: 274] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Boese AD, Martin JML, Handy NC. The role of the basis set: Assessing density functional theory. J Chem Phys 2003. [DOI: 10.1063/1.1589004] [Citation(s) in RCA: 157] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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van Heijnsbergen D, Fielicke A, Meijer G, von Helden G. Structure determination of gas-phase niobium and tantalum carbide nanocrystals via infrared spectroscopy. PHYSICAL REVIEW LETTERS 2002; 89:013401. [PMID: 12097042 DOI: 10.1103/physrevlett.89.013401] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2002] [Indexed: 05/23/2023]
Abstract
Niobium and tantalum carbide clusters have been isolated in the gas phase and irradiated with intense tunable infrared (IR) light. Stable neutral clusters are selectively ionized and subsequently detected in a mass spectrometer. By tuning the IR frequency, infrared multiphoton absorption spectra are obtained for a whole range of clusters. These mass-selective IR spectra lead to insights into the structures of small niobium and tantalum carbide clusters and nanocrystals.
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Affiliation(s)
- Deniz van Heijnsbergen
- FOM Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, NL-3439 MN Nieuwegein, The Netherlands
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Geometric and electronic structures of V2C2− and V2C2 studied by photoelectron spectroscopy and density-functional calculations. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(01)01358-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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