1
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Miyajima K, Mafuné F. Catalytic reactions of gas phase zirconium oxide clusters with NO and CO revealed by post heating. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.07.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2
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Yin S, Bernstein ER. Ethylene C-H Bond Activation by Neutral Mn2O5 Clusters under Visible Light Irradiation. J Phys Chem Lett 2016; 7:1709-1716. [PMID: 27099985 DOI: 10.1021/acs.jpclett.6b00541] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A photo excitation fast flow reactor coupled with a single-photon ionization (118 nm, 10.5 eV) time-of-flight mass spectrometry (TOFMS) instrument is used to investigate reactions of neutral MnmOn clusters with C2H4 under visible (532 nm) light irradiation. Association products Mn2O5(C2H4) and Mn3O6,7(C2H4) are observed without irradiation. Under light irradiation, the Mn2O5(C2H4) TOFMS feature decreases, and a new species, Mn2O5H2, is observed. This light-activated reaction suggests that the visible radiation can induce the chemistry, Mn2O5 + C2H4 + hv(532 nm) → Mn2O5*(C2H4) → Mn2O5H2 + C2H2. High barriers (0.67 and 0.59 eV) are obtained on the ground-state potential energy surface (PES); the reaction is barrierless and thermodynamically favorable on the first excited-state PES, as performed by time-dependent density functional theory calculations. The calculational and experimental results suggest that Mn2O5-like structures on manganese oxide surfaces are the appropriate active catalytic sites for visible light photocatalysis of ethylene dehydrogenation.
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Affiliation(s)
- Shi Yin
- Department of Chemistry, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Elliot R Bernstein
- Department of Chemistry, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University , Fort Collins, Colorado 80523, United States
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3
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Saha A, Raghavachari K. Electronic structures and water reactivity of mixed metal sulfide cluster anions. J Chem Phys 2014; 141:074305. [DOI: 10.1063/1.4892671] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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4
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Kim JB, Weichman ML, Neumark DM. Structural Isomers of Ti2O4 and Zr2O4 Anions Identified by Slow Photoelectron Velocity-Map Imaging Spectroscopy. J Am Chem Soc 2014; 136:7159-68. [DOI: 10.1021/ja502713v] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Jongjin B. Kim
- Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Marissa L. Weichman
- Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel M. Neumark
- Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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5
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Yin S, Bernstein ER. Experimental and theoretical studies of H2O oxidation by neutral Ti2O4,5 clusters under visible light irradiation. Phys Chem Chem Phys 2014; 16:13900-8. [DOI: 10.1039/c4cp00097h] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Ti2O5 cluster has a high activity for H2O oxidation under visible light irradiation in the gas phase.
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Affiliation(s)
- Shi Yin
- Department of Chemistry
- NSF ERC for Extreme Ultraviolet Science and Technology
- Colorado State University
- Fort Collins, USA
| | - Elliot R. Bernstein
- Department of Chemistry
- NSF ERC for Extreme Ultraviolet Science and Technology
- Colorado State University
- Fort Collins, USA
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6
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Saha A, Raghavachari K. Hydrogen evolution from water through metal sulfide reactions. J Chem Phys 2013; 139:204301. [DOI: 10.1063/1.4830096] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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7
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Wang ZC, Yin S, Bernstein ER. Generation and reactivity of putative support systems, Ce-Al neutral binary oxide nanoclusters: CO oxidation and C–H bond activation. J Chem Phys 2013; 139:194313. [DOI: 10.1063/1.4830406] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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8
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Ma JB, Xu B, Meng JH, Wu XN, Ding XL, Li XN, He SG. Reactivity of Atomic Oxygen Radical Anions Bound to Titania and Zirconia Nanoparticles in the Gas Phase: Low-Temperature Oxidation of Carbon Monoxide. J Am Chem Soc 2013; 135:2991-8. [DOI: 10.1021/ja311695t] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jia-Bi Ma
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
- Institut für Chemie, Technischen Universität Berlin, Strasse des
17. Juni 135, 10623 Berlin, Germany
| | - Bo Xu
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Jing-Heng Meng
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Xiao-Nan Wu
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
| | - Xun-Lei Ding
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
| | - Xiao-Na Li
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
| | - Sheng-Gui He
- Beijing National Laboratory
for Molecular Sciences, State Key Laboratory for Structural Chemistry
of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China
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9
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Wang ZC, Yin S, Bernstein ER. Gas-Phase Neutral Binary Oxide Clusters: Distribution, Structure, and Reactivity toward CO. J Phys Chem Lett 2012; 3:2415-2419. [PMID: 26292125 DOI: 10.1021/jz3008276] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Neutral binary (vanadium-cobalt) oxide clusters are generated and detected in the gas phase for the first time. Their reactivities toward carbon monoxide (CO) are studied both experimentally and theoretically. Experimental results suggest that neutral VCoO4 can react with CO to generate VCoO3 and CO2. Density functional theory studies show parallel results as well as provide detailed reaction mechanisms.
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Affiliation(s)
- Zhe-Chen Wang
- Department of Chemistry, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Shi Yin
- Department of Chemistry, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Elliot R Bernstein
- Department of Chemistry, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, United States
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10
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Dibble CJ, Akin ST, Ard S, Fowler CP, Duncan MA. Photodissociation of Cobalt and Nickel Oxide Cluster Cations. J Phys Chem A 2012; 116:5398-404. [DOI: 10.1021/jp302560p] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- C. J. Dibble
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556,
United States
| | - S. T. Akin
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556,
United States
| | - S. Ard
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556,
United States
| | - C. P. Fowler
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556,
United States
| | - M. A. Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556,
United States
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11
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Ding XL, Wu XN, Zhao YX, Ma JB, He SG. Double-Oxygen-Atom Transfer in Reactions of CemO2m+ (m=2-6) with C2H2. Chemphyschem 2011; 12:2110-7. [DOI: 10.1002/cphc.201100216] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Indexed: 11/12/2022]
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12
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Wu XN, Ma JB, Xu B, Zhao YX, Ding XL, He SG. Collision-Induced Dissociation and Density Functional Theory Studies of CO Adsorption over Zirconium Oxide Cluster Ions: Oxidative and Nonoxidative Adsorption. J Phys Chem A 2011; 115:5238-46. [DOI: 10.1021/jp200984r] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiao-Nan Wu
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - Jia-Bi Ma
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - Bo Xu
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - Yan-Xia Zhao
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - Xun-Lei Ding
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Sheng-Gui He
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
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13
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Han HL, Camacho C, Witek HA, Lee YP. Infrared absorption of methanol clusters (CH3OH)n with n = 2−6 recorded with a time-of-flight mass spectrometer using infrared depletion and vacuum-ultraviolet ionization. J Chem Phys 2011; 134:144309. [DOI: 10.1063/1.3572225] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Li S, Dixon DA. Molecular Structures and Energetics of the (ZrO2)n and (HfO2)n (n = 1−4) Clusters and Their Anions. J Phys Chem A 2010; 114:2665-83. [DOI: 10.1021/jp910310j] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Shenggang Li
- Chemistry Department, The University of Alabama, Shelby Hall, Box 870336, Tuscaloosa, Alabama 35487-0336
| | - David A. Dixon
- Chemistry Department, The University of Alabama, Shelby Hall, Box 870336, Tuscaloosa, Alabama 35487-0336
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15
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Xie Y, Dong F, Heinbuch S, Rocca JJ, Bernstein ER. Oxidation reactions on neutral cobalt oxide clusters: experimental and theoretical studies. Phys Chem Chem Phys 2009; 12:947-59. [PMID: 20066380 DOI: 10.1039/b915590b] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Reactions of neutral cobalt oxide clusters (Co(m)O(n), m = 3-9, n = 3-13) with CO, NO, C(2)H(2), and C(2)H(4) in a fast flow reactor are investigated by time of flight mass spectrometry employing 118 nm (10.5 eV) single photon ionization. Strong cluster size dependent behavior is observed for all the oxidation reactions; the Co(3)O(4) cluster has the highest reactivity for reactions with CO and NO. Cluster reactivity is also highly correlated with either one or more following factors: cluster size, Co(iii) concentration, the number of the cobalt atoms with high oxidation states, and the presence of an oxygen molecular moiety (an O-O bond) in the Co(m)O(n) clusters. The experimental cluster observations are in good agreement with condensed phase Co(3)O(4) behavior. Density functional theory calculations at the BPW91/TZVP level are carried out to explore the geometric and electronic structures of the Co(3)O(4) cluster, reaction intermediates, transition states, as well as reaction mechanisms. CO, NO, C(2)H(2), and C(2)H(4) are predicted to be adsorbed on the Co(ii) site, and react with one of the parallel bridge oxygen atoms between two Co(iii) atoms in the Co(3)O(4) cluster. Oxidation reactions with CO, NO, and C(2)H(2) on the Co(3)O(4) cluster are estimated as thermodynamically favorable and overall barrierless processes at room temperature. The oxidation reaction with C(2)H(4) is predicted to have a very small overall barrier (<0.23 eV). The oxygen bridge between two Co(iii) sites in the Co(3)O(4) cluster is responsible for the oxidation reactions with CO, NO, C(2)H(2), and C(2)H(4). Based on the gas phase experimental and theoretical cluster studies, a catalytic cycle for these oxidation reactions on a condensed phase cobalt oxide catalyst is proposed.
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Affiliation(s)
- Yan Xie
- Department of Chemistry, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, CO 80523, USA
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16
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Xie Y, Dong F, Heinbuch S, Rocca JJ, Bernstein ER. Investigation of the reactions of small neutral iron oxide clusters with methanol. J Chem Phys 2009; 130:114306. [DOI: 10.1063/1.3086724] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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17
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Dong F, Heinbuch S, Xie Y, Rocca JJ, Bernstein ER. Reactions of Neutral Vanadium Oxide Clusters with Methanol. J Phys Chem A 2009; 113:3029-40. [DOI: 10.1021/jp807589q] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Feng Dong
- Department of Chemistry, Department of Electrical and Computer Engineering, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523
| | - Scott Heinbuch
- Department of Chemistry, Department of Electrical and Computer Engineering, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523
| | - Yan Xie
- Department of Chemistry, Department of Electrical and Computer Engineering, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523
| | - Jorge J. Rocca
- Department of Chemistry, Department of Electrical and Computer Engineering, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523
| | - Elliot R. Bernstein
- Department of Chemistry, Department of Electrical and Computer Engineering, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523
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18
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Matsuda Y, Mikami N, Fujii A. Vibrational spectroscopy of size-selected neutral and cationic clusters combined with vacuum-ultraviolet one-photon ionization detection. Phys Chem Chem Phys 2009; 11:1279-90. [DOI: 10.1039/b815257h] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Xue W, Wang ZC, He SG, Xie Y, Bernstein ER. Experimental and Theoretical Study of the Reactions between Small Neutral Iron Oxide Clusters and Carbon Monoxide. J Am Chem Soc 2008; 130:15879-88. [PMID: 18975866 DOI: 10.1021/ja8023093] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wei Xue
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, Graduate School of the Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Zhe-Chen Wang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, Graduate School of the Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Sheng-Gui He
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, Graduate School of the Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Yan Xie
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, Graduate School of the Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Elliot R. Bernstein
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, Graduate School of the Chinese Academy of Sciences, Beijing 100080, People’s Republic of China, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
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20
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He SG, Xie Y, Dong F, Heinbuch S, Jakubikova E, Rocca JJ, Bernstein ER. Reactions of Sulfur Dioxide with Neutral Vanadium Oxide Clusters in the Gas Phase. II. Experimental Study Employing Single-Photon Ionization. J Phys Chem A 2008; 112:11067-77. [DOI: 10.1021/jp805744g] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Sheng-Gui He
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
| | - Yan Xie
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
| | - Feng Dong
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
| | - Scott Heinbuch
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
| | - Elena Jakubikova
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
| | - J. J. Rocca
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
| | - Elliot R. Bernstein
- Departments of Chemistry and Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523-1872, and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523-1320
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21
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Wang ZC, Xue W, Ma YP, Ding XL, He SG, Dong F, Heinbuch S, Rocca JJ, Bernstein ER. Partial Oxidation of Propylene Catalyzed by VO3 Clusters: A Density Functional Theory Study. J Phys Chem A 2008; 112:5984-93. [DOI: 10.1021/jp7115774] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Zhe-Chen Wang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Wei Xue
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Yan-Ping Ma
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Xun-Lei Ding
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Sheng-Gui He
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Feng Dong
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Scott Heinbuch
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Jorge J. Rocca
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
| | - Elliot R. Bernstein
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, P. R. China, Graduate School of Chinese Academy of Sciences, Beijing 100039, P. R. China, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523
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22
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Mok DK, Chau FT, Dyke JM, Lee EP. A combined ab initio and Franck–Condon simulation study of the photodetachment spectrum of ZrO2-. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.03.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Molek KS, Anfuso-Cleary C, Duncan MA. Photodissociation of Iron Oxide Cluster Cations. J Phys Chem A 2008; 112:9238-47. [DOI: 10.1021/jp8009436] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. S. Molek
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556
| | - C. Anfuso-Cleary
- 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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24
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Dong F, Heinbuch S, Xie Y, Rocca JJ, Bernstein ER, Wang ZC, Deng K, He SG. Experimental and Theoretical Study of the Reactions between Neutral Vanadium Oxide Clusters and Ethane, Ethylene, and Acetylene. J Am Chem Soc 2008; 130:1932-43. [DOI: 10.1021/ja076007z] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Feng Dong
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Scott Heinbuch
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Yan Xie
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Jorge J. Rocca
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Elliot R. Bernstein
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Zhe-Chen Wang
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Ke Deng
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
| | - Sheng-Gui He
- Department of Chemistry, Department of Electrical and Computer Engineering, NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523, Beijing National Laboratory for Molecular Science, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Haidian, Beijing 100080, China, and National Center of Nanoscience and Technology, Beijing 100080, People's Republic of China
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25
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Hachiya M, Matsuda Y, Suhara KI, Mikami N, Fujii A. Infrared predissociation spectroscopy of cluster cations of protic molecules, (NH[sub 3])[sub n]+], n=2–4 and (CH[sub 3]OH)[sub n]+], n=2,3. J Chem Phys 2008; 129:094306. [DOI: 10.1063/1.2971186] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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26
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Gong Y, Zhou M. Formation and Characterization of the Oxygen-Rich Hafnium Dioxygen Complexes: OHf(η2-O2)(η2-O3), Hf(η2-O2)3, and Hf(η2-O2)4. J Phys Chem A 2007; 111:8973-9. [PMID: 17718464 DOI: 10.1021/jp074531m] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hafnium atom oxidation by dioxygen molecules has been investigated using matrix isolation infrared absorption spectroscopy. The ground-state hafnium atom inserts into dioxygen to form primarily the previously characterized HfO(2) molecule in solid argon. Annealing allows the dioxygen molecules to diffuse and react with HfO(2) to form OHf(eta(2)-O(2))(eta(2)-O(3)), which is characterized as a side-on bonded oxo-superoxo hafnium ozonide complex. Under visible light (532 nm) irradiation, the OHf(eta(2)-O(2))(eta(2)-O(3)) complex either photochemically rearranges to a more stable Hf(eta(2)-O(2))(3) isomer, a side-on bonded di-superoxo hafnium peroxide complex, or reacts with dioxygen to form an unprecedented homoleptic tetra-superoxo hafnium complex: Hf(eta(2)-O(2))(4). The Hf(eta(2)-O(2))(4) complex is determined to possess a D(2d) geometry with a tetrahedral arrangement of four side-on bonded O(2) ligands around the hafnium atom, which thus presents an 8-fold coordination. These oxygen-rich complexes are photoreversible; that is, formation of Hf(eta(2)-O(2))(3) and Hf(eta(2)-O(2))(4) is accompanied by demise of OHf(eta(2)-O(2))(eta(2)-O(3)) under visible (532 nm) light irradiation and vice versa with UV (266 nm) light irradiation.
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Affiliation(s)
- Yu Gong
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Advanced Materials Laboratory, Fudan University, Shanghai 200433, People's Republic of China
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27
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Molek KS, Reed ZD, Ricks AM, Duncan MA. Photodissociation of Chromium Oxide Cluster Cations. J Phys Chem A 2007; 111:8080-9. [PMID: 17665887 DOI: 10.1021/jp073789+] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chromium oxide cluster cations, Cr(n)O(m)+, are produced by laser vaporization in a pulsed nozzle cluster source and detected with time-of-flight mass spectrometry. The mass spectrum exhibits a limited number of stoichiometries for each value of n, where m > n. The cluster cations are mass selected and photodissociated using the second (532 nm) or third (355 nm) harmonic output of a Nd:YAG laser. At either wavelength, multiphoton absorption is required to dissociate these clusters, which is consistent with their expected strong bonding. Cluster dissociation occurs via elimination of molecular oxygen, or by fission processes producing stable cation species and/or eliminating stable neutrals such as CrO3, Cr(2)O(5), or Cr(4)O(10). Specific cation clusters identified to be stable because they are produced repeatedly in the decomposition of larger clusters include Cr(2)O(4)+, Cr(3)O(6)+, Cr(3)O(7)+, Cr(4)O(9)+, and Cr(4)O(10)+.
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Affiliation(s)
- K S Molek
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
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28
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Wang WG, Wang ZC, Yin S, He SG, Ge MF. Reaction of Cationic Vanadium Oxide Clusters with Ethylene in a Flow Tube Reactor. CHINESE J CHEM PHYS 2007. [DOI: 10.1088/1674-0068/20/04/412-418] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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He SG, Xie Y, Guo Y, Bernstein ER. Formation, detection, and stability studies of neutral vanadium sulfide clusters. J Chem Phys 2007; 126:194315. [PMID: 17523812 DOI: 10.1063/1.2730828] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Neutral vanadium sulfide clusters are generated by the reaction of seeded hydrogen sulfide in a helium carrier gas with laser ablated vanadium metal within a supersonic nozzle. The exiting clusters are expanded into a vacuum in a molecular beam and are ionized by both ultraviolet (UV) and vacuum UV (VUV) laser radiation. The generated ions are detected by a time of flight mass spectrometer. With single photon ionization (SPI) employing VUV (118 nm) radiation, sulfur rich clusters (V(m)S(n), n>m+1) and hydrogen containing clusters (V(m)S(n)H(x), x>0) are observed. With multiphoton ionization (MPI) through nanosecond UV (193 nm) radiation, these sulfur rich and hydrogen containing clusters cannot be observed, indicating severe fragmentation generated by MPI and the importance of SPI in determining the neutral vanadium sulfide cluster distribution. With MPI through femtosecond UV (226 nm) radiation, a few sulfur rich and hydrogen containing clusters are detected, but most clusters observed by SPI are still undetected even by femtosecond MPI. Density functional theory calculations are applied to optimize energies and structures of the clusters with m=1-3 and n=0-7. The experimental results are well interpreted based on the calculations. The calculated and experimental results for vanadium sulfides are compared with those of vanadium oxides in literature.
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Affiliation(s)
- Sheng-Gui He
- Department of Chemistry, Colorado State University, 1872 Campus Delivery, Fort Collins, Colorado 80523, USA
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30
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Gong Y, Zhang Q, Zhou M. Matrix Isolation Infrared Spectroscopic and Theoretical Study of Group IV Metal Oxide Clusters: M2O2 and M2O4. J Phys Chem A 2007; 111:3534-9. [PMID: 17439109 DOI: 10.1021/jp0711388] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dinuclear titanium, zirconium, and hafnium oxide clusters, M2O2 and M2O4 (M = Ti, Zr, Hf) have been prepared and characterized by matrix isolation infrared spectroscopy and quantum chemical calculations. The M2O2 clusters were formed through the reactions of metal dimers and O2 in solid argon upon sample annealing. Theoretical calculations indicate that the Ti2O2 cluster has a singlet ground state with a nonplanar cyclic C(2v) structure with a strong Ti-Ti bond, while the Zr2O2 and Hf2O2 clusters have planar cyclic structures. The M2O4 clusters were characterized to have a closed-shell singlet ground state with a nonplanar C2h symmetry, which were formed from the dimerization of the metal dioxide molecules.
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Affiliation(s)
- Yu Gong
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Advanced Materials Laboratory, Fudan University, Shanghai 200433, P.R. China
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31
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Dong F, Heinbuch S, He SG, Xie Y, Rocca JJ, Bernstein ER. Formation and distribution of neutral vanadium, niobium, and tantalum oxide clusters: Single photon ionization at 26.5eV. J Chem Phys 2006; 125:164318. [PMID: 17092084 DOI: 10.1063/1.2358980] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Neutral vanadium, niobium, and tantalum oxide clusters are studied by single photon ionization employing a 26.5 eV/photon soft x-ray laser. During the ionization process the metal oxide clusters are almost free of fragmentation. The most stable neutral clusters of vanadium, niobium, and tantalum oxides are of the general form (MO2)0,1(M2O5)y. M2O5 is identified as a basic building unit for these three neutral metal oxide species. Each cluster family (Mm, m=1,...,9) displays at least one oxygen deficient and/or oxygen rich cluster stoichiometry in addition to the above most stable species. For tantalum and niobium families with even m, oxygen deficient clusters have the general formula (MO2)2(M2O5)y. For vanadium oxide clusters, oxygen deficient clusters are detected for all cluster families Vm (m=1,[ellipsis (horizontal)],9), with stable structures (VO2)x(V2O5)y. Oxygen rich metal oxide clusters with high ionization energies (IE>10.5 eV, 118 nm photon) are detected with general formulas expressed as (MO2)2 (M2O5)y O1,2,3. Oxygen rich clusters, in general, have up to three attached hydrogen atoms, such as VO3H1,2, V2O5H1,2, Nb2O5H1,2, etc.
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Affiliation(s)
- F Dong
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA
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32
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Matsuda Y, Mori M, Hachiya M, Fujii A, Mikami N. Infrared spectroscopy of size-selected neutral clusters combined with vacuum-ultraviolet-photoionization mass spectrometry. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.02.104] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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33
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Molek KS, Jaeger TD, Duncan MA. Photodissociation of vanadium, niobium, and tantalum oxide cluster cations. J Chem Phys 2005; 123:144313. [PMID: 16238397 DOI: 10.1063/1.2050650] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Transition-metal oxide clusters of the form M(n)O(m) (+)(M=V,Nb,Ta) are produced by laser vaporization in a pulsed nozzle cluster source and detected with time-of-flight mass spectrometry. Consistent with earlier work, cluster oxides for each value of n produce only a limited number of stoichiometries, where m>n. The cluster cations are mass selected and photodissociated using the second (532 nm) or third (355 nm) harmonic of a Nd:YAG (yttrium aluminum garnet) laser. All of these clusters require multiphoton conditions for dissociation, consistent with their expected strong bonding. Dissociation occurs by either elimination of oxygen or by fission, repeatedly producing clusters having the same specific stoichiometries. In oxygen elimination, vanadium species tend to lose units of O(2), whereas niobium and tantalum lose O atoms. For each metal increment n, oxygen elimination proceeds until a terminal stoichiometry is reached. Clusters having this stoichiometry do not eliminate more oxygen, but rather undergo fission, producing smaller M(n)O(m) (+) species. The smaller clusters produced as fission products represent the corresponding terminal stoichiometries for those smaller n values. The terminal stoichiometries identified are the same for V, Nb, and Ta oxide cluster cations. This behavior suggests that these clusters have stable bonding networks at their core, but additional excess oxygen at their periphery. These combined results determine that M(2)O(4) (+), M(3)O(7) (+), M(4)O(9) (+), M(5)O(12) (+), M(6)O(14) (+), and M(7)O(17) (+) have the greatest stability for V, Nb, and Ta oxide clusters.
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Affiliation(s)
- K S Molek
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
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Guo YQ, Greenfield M, Bernstein ER. Decomposition of nitramine energetic materials in excited electronic states: RDX and HMX. J Chem Phys 2005; 122:244310. [PMID: 16035760 DOI: 10.1063/1.1929741] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ultraviolet excitation (8-ns duration) is employed to study the decomposition of RDX (1,3,5-trinitro-1,3,5-triazacyclohexane) and HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane) from their first excited electronic states. Isolated RDX and HMX are generated in the gas phase utilizing a combination of matrix-assisted laser desorption and supersonic jet expansion techniques. The NO molecule is observed as one of the initial dissociation products by both time-of-flight mass spectroscopy and laser-induced fluorescence spectroscopy. Four different vibronic transitions of NO are observed: A (2)Sigma(v(') = 0)<--X (2)Pi(v(") = 0,1,2,3). Simulations of the NO rovibronic intensities for the A<--X transitions show that dissociated NO from RDX and HMX is rotationally cold (approximately 20 K) and vibrationally hot (approximately 1800 K). Another potential initial product of RDX and HMX excited state dissociation could be OH, generated along with NO, perhaps from a HONO intermediate species. The OH radical is not observed in fluorescence even though its transition intensity is calculated to be 1.5 times that found for NO per radical generated. The HONO intermediate is thereby found not to be an important pathway for the excited electronic state decomposition of these cyclic nitramines.
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Affiliation(s)
- Y Q Guo
- Department of Chemistry, Colorado State University, Fort Collins, 80523, USA
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35
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Matsuda Y, Bernstein ER. Identification, Structure, and Spectroscopy of Neutral Vanadium Oxide Clusters. J Phys Chem A 2005; 109:3803-11. [PMID: 16833696 DOI: 10.1021/jp040718r] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neutral vanadium oxide clusters are studied by photoionization time-of-flight (TOF) mass spectroscopy, electronic spectroscopy, and density functional theory (DFT) calculations. Mass spectra of vanadium oxide clusters are observed by photoionization with lasers of three different wavelengths: 118, 193, and 355 nm. Mechanisms of 118 nm single photon ionization and 193 and 355 nm multiphoton ionization/fragmentation of vanadium oxide clusters are discussed on the basis of observed mass spectral patterns and line widths of the mass spectral features. Only the 118 nm laser light can ionize vanadium oxide neutral species by single photon ionization without fragmentation. The stable vanadium oxide neutral clusters under saturated oxygen growth conditions are found to be of the form (VO2)x(V2O5)y. Structures of the first few members of this series of clusters are determined through high level DFT calculations. Fragmentation of this series of clusters through 355 and 193 nm multiphoton ionization processes is discussed in light of these calculated structures. The B(2)B2 <-- X(2)A1 transition is observed for the VO2 neutral species, and nu1 and nu2 vibrations are assigned for both electronic states. From this spectrum, the VO2 rotational and vibrational temperatures are found to be approximately 50 and approximately 700 K, respectively.
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Affiliation(s)
- Yoshiyuki Matsuda
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, USA
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36
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Matsuda Y, Bernstein ER. On the Titanium Oxide Neutral Cluster Distribution in the Gas Phase: Detection through 118 nm Single-Photon and 193 nm Multiphoton Ionization. J Phys Chem A 2004; 109:314-9. [PMID: 16833349 DOI: 10.1021/jp040670h] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Titanium oxide clusters are generated in a supersonic expansion by laser ablation of the metal and reaction with oxygen (0.1-6%) in He expansion gas. Mass spectra of the titanium oxide clusters are observed by photoionization with lasers of three different wavelengths: 118, 193, and 355 nm. Only the 118 nm (10.5 eV) light can ionize Ti(m)O(n) neutral clusters without fragmentation. Both the 193 nm (6.4 eV) and 355 nm (3.5 eV) multiphoton ionization cause fragmentation of the neutral clusters during the ionization process and, thus, can complicate the determination of the stable neutral Ti(m)O(n) gas-phase species. Employing 118 nm single-photon ionization and line-width data, the Ti(m)O(2m) and Ti(m)O(2m+1) series are found to be the most stable neutral cluster species for high oxygen content in the expansion gas. Fragmentation during the multiphoton ionization process for 193 nm light yields the cluster ions Ti(m)O(2m-1,-2)+. These ions are formed by the loss of one or two oxygen atoms from Ti(m)O(2m,2m+1) neutral species. The dominant cluster growth process is suggested to be through the addition of TiO2 species. For low oxygen content (<2%) in the expansion gas, oxygen-deficient clusters of the form Ti(m)O(2m-1,-2) are also observed. These latter series are not fragmented by the 193 nm ionization process.
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Affiliation(s)
- Yoshiyuki Matsuda
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, USA
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