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Zhang J. The Theoretical Calculation of the Cu Isotope Fractionation Effect in Solution/Hydrothermal Solution Systems. Molecules 2024; 29:2582. [PMID: 38893459 PMCID: PMC11173797 DOI: 10.3390/molecules29112582] [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: 04/15/2024] [Revised: 05/18/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024] Open
Abstract
Copper (Cu) is an important transition metal, and its isotopes have important applications in geology, environmental science, soil science, and other fields. Cu isotope fractionation can occur in many natural processes. However, the mechanism of Cu isotope fractionation in solution/hydrothermal solution systems is not very clear. In this study, the fractionation effects of complexes of Cu(I) and Cu(II) in solution/hydrothermal solution systems were systematically studied by means of an ab initio method based on first principles. In the simulation of an aqueous solution system, the theoretical treatment method used is the "water-droplet" method. The results show that the heavy Cu isotope (65Cu) enrichment capacity of the Cu-bearing complex solutions is greatly affected by the ligand types both for Cu(I) and Cu(II). For Cu(I) complex solutions, the heavy Cu isotope enrichment sequence is [Cu(HS)2]-·(H2O)42 > [Cu(HS)(H2O)]·(H2O)42 ≈ [Cu(HS)(H2S)]·(H2O)42 > [CuCl]·(H2O)42 > [CuCl2]-·(H2O)42 > [CuCl3]2-·(H2O)42. For the aqueous solutions of Cu(II) with an inorganic ligand (such as H2O, OH-, NO3-, SO42- and CN-), the order of heavy Cu isotope enrichment is as follows: [Cu(H2O)6]2+·(H2O)42 > [Cu(NO3)2]·(H2O)42 > [Cu(OH)2]·(H2O)42 > [CuSO4(H2O)3]·(H2O)42 > [CuNO3(H2O)4]+·(H2O)42 > [CuCN]+·(H2O)42. For the Cu(II) complex solutions with a halogen as ligands, the change order of 1000lnβ is [CuCl]+·(H2O)42 > [CuCl2]·(H2O)42 > [CuBr2]·(H2O)42 > [CuCl3]-·(H2O)42. The sequence of 1000lnβ for Cu(II) organic complex aqueous solutions is [Cu(HOC6H4COO)]+·(H2O)42 > [Cu(CH3CH2COO)]+·(H2O)42 > [Cu(COOHCOO)]+·(H2O)42. The calculation also found that for Cu(I) complex aqueous solutions, the difference in Cu isotope fractionation parameters (1000lnβ) between [CuCl2]-·(H2O)42 and [Cu(HS)2]-·(H2O)42 is relatively large. At 100 °C, the 1000lnβ of the two species are 1.14 and 1.55 (‱), respectively. The difference between the two could be reached up to 0.41 (‱). The Cu isotope fractionation parameter obtained with the "water droplet" method is also very different from the results of previous studies, which indicate that the Cu isotope fractionation behavior of the two is similar. At the same time, the exciting discovery is that the enrichment capacity of heavy Cu isotopes is significantly different between Cu(I) complex aqueous solutions and Cu(II) complex aqueous solutions. At 100 °C, the 1000lnβ of 6 Cu(I) complex aqueous solutions and 13 Cu(II) complex aqueous solutions ranged from 0.90 to 1.55 and 2.24 to 3.25(‱), respectively. It also shows that the REDOX reaction has a significant effect on the Cu isotope fractionation, especially in ore-forming fluids. Therefore, the ligand type is a factor that cannot be ignored when considering the mechanism of Cu isotope fractionation in solution/hydrothermal solution systems. Whether the solvation effect of an aqueous solution is considered or not has a great influence on the numerical values of the final Cu isotope fractionation factors. Hence, the solvation effect of an aqueous solution is an essential determinant in the theoretical calculation of the Cu isotope fractionation factors for Cu-bearing complex solutions.
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Affiliation(s)
- Jixi Zhang
- School of Geography and Environmental Science, Guizhou Normal University, Guiyang 550001, China;
- School of Karst Science, Guizhou Normal University/State Engineering Technology Institute for Karst Desertification, Guiyang 550001, China
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Kong Q, Li Z, Zhao Y, Wei C, Qiu G, Wei C. Investigation of the fate of heavy metals based on process regulation-chemical reaction-phase distribution in an A-O 1-H-O 2 biological coking wastewater treatment system. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 247:234-241. [PMID: 31247370 DOI: 10.1016/j.jenvman.2019.06.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/29/2019] [Accepted: 06/13/2019] [Indexed: 06/09/2023]
Abstract
Regulation mechanism of typical substances including OH-, CN-, SCN-, S2-, NH3 on the distribution of heavy metals was investigated in coking wastewater treatment plant with our self-designed Anaerobic-Oxic-Hydrolytic-Oxic (A-O1-H-O2) system through engineering data exposure and computational density functional theory (DFT) verification. The results showed that coking sludge had superior enrichment ability for heavy metals, especially for the sludge from the A and H tanks. The enrichment ratio of the 8 heavy metals including Cd, Pb, Ni, Zn, Cu, Hg, Cr and As in coking waste sludge was found to be 6232 (comparing to these in the influent wastewater of A-O1-H-O2 system). The distribution of 8 heavy metals was closely related to their chemical (precipitation and/or complexation) and biochemical reaction potential with OH-, CN-, SCN-, S2-, NH3 in the A-O1-H-O2 system. The regulation mechanism of these precipitation and/or complexation agents on heavy metals was confirmed by DFT calculation. The stable energy of complexes formed between typical compounds and common heavy metal ions follow the order: OH: Cu2+>Pb2+>Zn2+>Cd2+>Hg2+>Ni2+; S2-: Pb2+>Cu2+>Zn2+>Cd2+>Hg2+>Ni2+; CN-: Zn2+>Cu2+>Cd2+>Hg2+>Pb2+>Ni2+; SCN-: Zn2+>Cd2+>Pb2+>Hg2+>Cu2+>Ni2+; NH3: Cu2+>Zn2+>Cd2+>Pb2+>Hg2+>Ni2+, providing reference for the judgement of which metal ions were preferentially combined with the typical compounds in coking wastewater. The results of this paper indicated that the enrichment of heavy metal ions in coking wastewater can be achieved by process design combined with the control of operating conditions (dissolved oxygen, hydraulic retention time, sludge retention time and pH), basing on the nature of heavy metal ions. Finally, the separation and differential management of heavy metals can be achieved.
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Affiliation(s)
- Qiaoping Kong
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Zemin Li
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Yasi Zhao
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Cong Wei
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Guanglei Qiu
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, 510006, PR China
| | - Chaohai Wei
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou, 510006, PR China.
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3
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Weinhold F. Polyion Covalency: Exotic Species from the Unexplored World of Electrostatically Shielded Molecular Ion Chemistry. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201708691] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry; University of Wisconsin; Madison Wisconsin 53706 USA
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4
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Weinhold F. Polyion Covalency: Exotic Species from the Unexplored World of Electrostatically Shielded Molecular Ion Chemistry. Angew Chem Int Ed Engl 2017; 56:14577-14581. [PMID: 28977727 DOI: 10.1002/anie.201708691] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Indexed: 12/21/2022]
Abstract
Standard quantum chemical methods have been employed to describe a variety of kinetically stable polyionic molecular species that are trapped in appreciable potential wells by chemical bonding forces, despite powerful electrostatic opposition that challenges conventional chemical detection and characterization. The studied species are covalent or dative analogs of "anti-electrostatic" hydrogen-bonded (AEHB) species, all illustrating how short-range quantum covalency can overcome the powerful "shielding" opposition of long-range electrostatic forces to form highly charged molecular species, analogous to known neutral or singly ionic counterparts. Computational predictions of representative structural, spectroscopic, and NBO-based electronic signatures of multiply charged analogs of common neutral species (CH3 CH3 , CO2 , FeCO) are provided to suggest the unique material properties characteristic of this shielded domain of polyionic chemical phenomena.
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Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin, 53706, USA
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5
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Song X, Li S, Jiang Z, Zhang Y. Theoretical study on structures and infrared spectroscopy of Cu2+(H2O)Ar n (n = 1–4). RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2017. [DOI: 10.1134/s003602441709031x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Tisato F, Forrer D, Tamburini S, Vittadini A, Traldi P, Porchia M. Interaction products of cytotoxic Cu(I) complexes with different solvent mixtures: an electrospray ionization mass spectrometry and density functional theory study. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:179-192. [PMID: 27806439 DOI: 10.1002/rcm.7781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/28/2016] [Accepted: 10/28/2016] [Indexed: 06/06/2023]
Abstract
RATIONALE [Cu(P)4 ][BF4 ]-type complexes (P = tertiary phosphine) have shown significant antitumor activity. This biological property appears to be activated via formation of coordinative unsaturated [Cu(P)n ]+ species (n < 4), that may interact with various molecules starting from the solvent(s) in which they are dissolved. Aim of our study was to investigate the interaction of these species with different solvent mixtures. METHODS The interaction has been investigated by electrospray ionization mass spectrometry, and the interaction products have been characterized by multiple collisional experiments, using an ion trap mass instrument. Density functional theory (DFT) calculation studies, using a meta-hybrid exchange correlation (xc) functional and an implicit solvent model, were employed to investigate the equilibrium distribution of species in solution. RESULTS Depending on the nature of the solvent mixture and coordinated phosphine, three [Cu(P)4 ][BF4 ]-type complexes undergo dissociation with formation of [Cu(P)2 ]+ , [Cu(P)(solv)]+ and [Cu(solv)2 ]+ species (solv = solvent). Preferred collisional-induced fragmentation pathways provide qualitative information on the selectivity of [Cu(P)n ]+ for specific solvents and donor atoms. Formation free energies and equilibrium constants pertaining to [CuI (PTA)n ]+ , [CuI/II (solv)n ]m+ (n ≤ 4; m = 1, 2) and [CuI (PTA)2-k (sol)k ]+ (k = 1, 2) provide a comprehensive picture of equilibria in solution. CONCLUSIONS Dimethyl sulfoxide (DMSO) and acetonitrile (MeCN) strongly affect [Cu(P)n ]+ assemblies producing mixed-ligand [Cu(P)(DMSO)]+ and [Cu(P)(MeCN)]+ species. Excess of both DMSO and MeCN solvents are able to fully displace coordinated phosphines giving [Cu(solv)2 ]+ -type adducts. The presence of phosphines in the native complex is mandatory to retain the reduced oxidation state of copper. Instead, the more labile [CuI (MeCN)4 ]+ complex dissolved in DMSO and MeCN displays a combination of Cu(I) and Cu(II) adducts. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
| | - Daniel Forrer
- CNR - ICMATE, Corso Stati Uniti 4, 35127, Padova, Italy
| | | | | | - Pietro Traldi
- CNR - ICMATE, Corso Stati Uniti 4, 35127, Padova, Italy
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Dobrokhotova ZV, Gogoleva NV, Zorina‐Tikhonova EN, Kiskin MA, Chernyshev VV, Emelina AL, Bukov MA, Goloveshkin AS, Bushmarinov IS, Sidorov AA, Bogomyakov AS, Kovba ML, Novotortsev VM, Eremenko IL. The Use of Malonate Coordination Polymers with Cu
II
and Ba
II
Atoms for Barium Cuprate Preparation. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201500243] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zhanna V. Dobrokhotova
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
| | - Natalya V. Gogoleva
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
| | - Ekaterina N. Zorina‐Tikhonova
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
| | - Mikhail A. Kiskin
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
| | - Vladimir V. Chernyshev
- Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, 119991 Moscow, GSP‐1, Russian Federation
| | - Anna L. Emelina
- Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, 119991 Moscow, GSP‐1, Russian Federation
| | - Mikhail A. Bukov
- Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, 119991 Moscow, GSP‐1, Russian Federation
| | - Alexander S. Goloveshkin
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova str. 28, 119991 Moscow, GSP‐1, Russian Federation
| | - Ivan S. Bushmarinov
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova str. 28, 119991 Moscow, GSP‐1, Russian Federation
| | - Aleksey A. Sidorov
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
| | - Artem S. Bogomyakov
- International Tomography Centre, Siberian Branch, Russian Academy of Sciences, Institutskaya str. 3a, 630090 Novosibirsk, Russian Federation
| | - Maksim L. Kovba
- Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, 119991 Moscow, GSP‐1, Russian Federation
| | - Vladimir M. Novotortsev
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
| | - Igor L. Eremenko
- N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP‐1, Russian Federation, http://www.igic.ras.ru/
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8
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DiTucci MJ, Heiles S, Williams ER. Role of Water in Stabilizing Ferricyanide Trianion and Ion-Induced Effects to the Hydrogen-Bonding Water Network at Long Distance. J Am Chem Soc 2015; 137:1650-7. [DOI: 10.1021/ja5119545] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Matthew J. DiTucci
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
| | - Sven Heiles
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
| | - Evan R. Williams
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
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9
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Armentrout PB, Sweeney AF. Hydrated copper ion chemistry: guided ion beam and computational investigation of Cu2+(H2O)n (n = 7-10) complexes. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2015; 21:497-516. [PMID: 26307731 DOI: 10.1255/ejms.1334] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cross sections for the threshold collision-induced dissociation of Cu(2+)(H(2)O)(n), where n = 8 - 10, are measured using a guided ion beam tandem mass spectrometer. The primary dissociation pathway is found to be loss of a single water molecule followed by the sequential loss of additional water molecules until n = 8, at which point charge separation to form CuOH(+)(H(2)O)(4) (+) H(+)(H(2)O)(3) is observed to occur at a slightly lower energy than loss of a water molecule. Competition from charge separation prohibits the formation of appreciable amounts of the n = 7 or smaller complexes as reactants in the source. These findings indicate that Cu(2+) has a critical size of 8. Analysis of the data using statistical modeling techniques that account for energy distributions and lifetime effects yields primary and sequential bond dissociation energies (BDEs) for loss of one and two water molecules from n = 8 - 10 complexes as well as the barrier for charge separation from n = 8. More speculative analysis extends the thermochemistry obtained down to n = 5 and 6. Theoretical BDEs are determined from quantum chemical calculations using structures optimized at the B3LYP/6 311(+)G(d,p) level along with the lowest-energy isomers suggested by single point energies at the MP2(full), M06, B3LYP, and B3P86 levels of theory using a 6- 311(+)G(2d,2p) basis set. BDEs at 0K are converted to 298 K thermodynamic values using a rigid rotor/harmonic oscillator approximation. Experimental and theoretical entropies of activation suggest that a third solvent shell forms at n = 9, in accord with previous findings. The present work represents the first experimentally determined hydration enthalpies for the Cu(2+)(H(2)O)n system.
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Affiliation(s)
- Peter B Armentrout
- Department of Chemistry, University of Utah, 315 South 1400 East, Rm 2020, Salt Lake City, Utah 84112, United States.
| | - Andrew F Sweeney
- Department of Chemistry, University of Utah, 315 South 1400 East, Rm 2020, Salt Lake City, Utah 84112, United States.
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10
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Hurtado M, Monte M, Lamsabhi AM, Yáñez M, Mó O, Salpin JY. Modeling Interactions between an Amino Acid and a Metal Dication: Cysteine-Calcium(II) Reactions in the Gas Phase. Chempluschem 2013; 78:1124-1133. [DOI: 10.1002/cplu.201300166] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Indexed: 11/11/2022]
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11
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Eizaguirre A, Mó O, Yáñez M, Tortajada J, Salpin JY. Unimolecular reactivity of the [urea-Sr]2+ complex, a metastable dication in the gas phase: an experimental and theoretical perspective. J Phys Chem B 2013; 117:2088-95. [PMID: 23343443 DOI: 10.1021/jp312466t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The interactions between urea and Sr(2+) in the gas phase have been investigated by combining electrospray ionization/mass spectrometry techniques and density functional and high-level ab initio molecular orbital calculations. Our theoretical survey indicates that [Sr(urea)](2+) adducts are thermodynamically stable with respect to direct Coulomb explosions. However, after isomerization, some of the local minima of the PES are thermodynamically unstable with respect to the formation of NH(4)(+), but kinetically metastable. The loss of neutral fragments with the concomitant generation of lighter doubly charged fragment ions, namely, [(H(3)N)Sr](2+) and [(HNCO)]Sr(2+), compete with the aforementioned Coulomb explosion processes yielding NH(4)(+) + [(NCO)Sr](+) and [(H(2)N)Sr](+) + [H(2)NCO](+), although the former processes dominate. Hence, both singly and doubly charged species are detected as dissociation products. Quite importantly, the observed eliminations of NH(3) or HNCO lead to the formation of new doubly charged species, which turn out to be thermodynamically stable.
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Affiliation(s)
- Ane Eizaguirre
- Departamento de Química, Módulo 13, Facultad de Ciencias, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco 28049, Madrid, Spain
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12
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Reactivity of [Ba(H2O)n⩽2]2+ with neutral molecules in the gas-phase: An experimental and DFT study. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.04.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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13
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Spezia R, Cimas A, Gaigeot MP, Salpin JY, Song K, Hase WL. Collision induced dissociation of doubly-charged ions: Coulomb explosion vs. neutral loss in [Ca(urea)]2+ gas phase unimolecular reactivity via chemical dynamics simulations. Phys Chem Chem Phys 2012; 14:11724-36. [PMID: 22828785 DOI: 10.1039/c2cp41379e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper we report different theoretical approaches to study the gas-phase unimolecular dissociation of the doubly-charged cation [Ca(urea)](2+), in order to rationalize recent experimental findings. Quantum mechanical plus molecular mechanical (QM/MM) direct chemical dynamics simulations were used to investigate collision induced dissociation (CID) and rotational-vibrational energy transfer for Ar + [Ca(urea)](2+) collisions. For the picosecond time-domain of the simulations, both neutral loss and Coulomb explosion reactions were found and the differences in their mechanisms elucidated. The loss of neutral urea subsequent to collision with Ar occurs via a shattering mechanism, while the formation of two singly-charged cations follows statistical (or almost statistical) dynamics. Vibrational-rotational energy transfer efficiencies obtained for trajectories that do not dissociate during the trajectory integration were used in conjunction with RRKM rate constants to approximate dissociation pathways assuming complete intramolecular vibrational energy redistribution (IVR) and statistical dynamics. This statistical limit predicts, as expected, that at long time the most stable species on the potential energy surface (PES) dominate. These results, coupled with experimental CID from which both neutral loss and Coulomb explosion products were obtained, show that the gas phase dissociation of this ion occurs by multiple mechanisms leading to different products and that reactivity on the complicated PES is dynamically complex.
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Affiliation(s)
- Riccardo Spezia
- Université d'Evry Val d'Essonne, Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, UMR 8587 CNRS-CEA-UEVE, Evry, France.
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Carl DR, Armentrout PB. Experimental Investigation of the Complete Inner Shell Hydration Energies of Ca2+: Threshold Collision-Induced Dissociation of Ca2+(H2O)x Complexes (x = 2–8). J Phys Chem A 2012; 116:3802-15. [DOI: 10.1021/jp301446v] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Damon R. Carl
- Department
of Chemistry, University of Utah, 315 S. 1400 E. Room 2020, Salt Lake City, Utah
84112, United States
| | - P. B. Armentrout
- Department
of Chemistry, University of Utah, 315 S. 1400 E. Room 2020, Salt Lake City, Utah
84112, United States
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15
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El-Nahas AM, Khedr GE, Emam SM. Thermodynamic and kinetic stability of magnesium dication solvated by tetramethylethylenediamine. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2011.09.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Chu IK, Laskin J. Formation of peptide radical ions through dissociative electron transfer in ternary metal-ligand-peptide complexes. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2011; 17:543-556. [PMID: 22274945 DOI: 10.1255/ejms.1156] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The formation and fragmentation of odd-electron ions of peptides and proteins is of interest to applications in biological mass spectrometry. Gas-phase redox chemistry occurring during collision-induced dissociation of ternary metal-ligand-peptide complexes enables the formation of a variety of peptide radicals, including the canonical radical cations, M(+•), radical dications, [M+H](2+•), radical anions, [M-2H](-•) and phosphorylated radical cations. In addition, odd-electron peptide ions with well-defined initial location of the radical site are produced through side-chain losses from the radical ions. Subsequent fragmentation of these species provides information regarding the role of charge and location of the radical site on the competition between radical-induced and proton-driven fragmentation of odd-electron peptide ions. This account summarizes current understanding of the factors that control the efficiency of the intramolecular electron transfer (ET) in ternary metal-ligand-peptide complexes resulting in formation of odd-electron peptide ions. Specifically, we discuss the effect of the metal center, the ligand and the peptide structure on the competition between the ET, proton transfer (PT) and loss of neutral peptide and neutral peptide fragments from the complex. Fundamental studies of the structures, stabilities and the energetics and dynamics of fragmentation of these complexes are also important for detailed molecular-level understanding of photosynthesis and respiration in biological systems.
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Affiliation(s)
- Ivan K Chu
- Department of Chemistry, The University of Hong Kong, Hong Kong, China.
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Corral I, Yáñez M. [MLn]2+ doubly charged systems: modeling, bonding, life times and unimolecular reactivity. Phys Chem Chem Phys 2011; 13:14848-64. [DOI: 10.1039/c1cp20622b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Jeanvoine Y, Spezia R. Cu2+ binding chalcogen–chalcogen bridges: A problematic case for DFT. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.theochem.2010.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Song T, Lam CNW, Ng DCM, Orlova G, Laskin J, Fang DC, Chu IK. Experimental and computational studies of the macrocyclic effect of an auxiliary ligand on electron and proton transfers within ternary copper(II)-histidine complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2009; 20:972-984. [PMID: 19230704 DOI: 10.1016/j.jasms.2009.01.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2008] [Revised: 01/13/2009] [Accepted: 01/13/2009] [Indexed: 05/27/2023]
Abstract
The dissociation of [Cu(II)(L)His](*2+) complexes [L = diethylenetriamine (dien) or 1,4,7-triazacyclononane (9-aneN(3))] bears a strong resemblance to the previously reported behavior of [Cu(II)(L)GGH](*2+) complexes. We have used low-energy collision-induced dissociation experiments and density functional theory (DFT) calculations at the B3LYP/6-31+G(d) level to study the macrocyclic effect of the auxiliary ligands on the formation of His(*+) from prototypical [Cu(II)(L)His](*2+) systems. DFT revealed that the relative energy barriers of the same electron-transfer (ET) dissociation pathways of [Cu(II)(9-aneN(3))His](*2+) and [Cu(II)(dien)His](*2+) are very similar, with the ET reactions of [Cu(II)(9-aneN(3))His](*2+) leading to the generation of two distinct His(*+) species; in contrast, the proton transfer (PT) dissociation pathways of [Cu(II)(9-aneN(3))His](*2+) and [Cu(II)(dien)His](*2+) differ considerably. The PT reactions of [Cu(II)(9-aneN(3))His](*2+) are associated with substantially higher barriers (>13 kcal/mol) than those of [Cu(II)(dien)His](*2+). Thus, the sterically encumbered auxiliary 9-aneN(3) ligand facilitates ET reactions while moderating PT reactions, allowing the formation of hitherto nonobservable histidine radical cations.
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Affiliation(s)
- Tao Song
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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22
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Révész Á, Sztáray B, Schröder D, Franzreb K, Fišer J, Price SD, Roithová J. The diatomic dication PO2+. Phys Chem Chem Phys 2009; 11:6192-8. [DOI: 10.1039/b902843a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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23
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Pavelka M, Burda JV. Computational study of redox active centres of blue copper proteins: a computational DFT study. Mol Phys 2008. [DOI: 10.1080/00268970802672684] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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24
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Coyne JP, Ball DW. Alpha particle chemistry. On the formation of stable complexes between He2+ and other simple species: implications for atmospheric and interstellar chemistry. J Mol Model 2008; 15:35-40. [DOI: 10.1007/s00894-008-0371-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Accepted: 09/22/2008] [Indexed: 10/21/2022]
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25
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Siu CK, Ke Y, Guo Y, Hopkinson AC, Siu KWM. Dissociations of copper(II)-containing complexes of aromatic amino acids: radical cations of tryptophan, tyrosine, and phenylalanine. Phys Chem Chem Phys 2008; 10:5908-18. [PMID: 18818845 DOI: 10.1039/b807692h] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dissociations of two types of copper(II)-containing complexes of tryptophan (Trp), tyrosine (Tyr), or phenylalanine (Phe) are described. The first type is the bis-amino acid complex, [Cu(II)(M)(2)].(2+), where M = Trp, Tyr, or Phe; the second [Cu(II)(4Cl-tpy)(M)].(2+), where 4Cl-tpy is the tridendate ligand 4'-chloro-2,2':6',2''-terpyridine. Dissociations of the Cu(ii) bis-amino acid complexes produce abundant radical cation of the amino acid, M.(+), and/or its secondary products. By contrast, dissociations of the 4Cl-tpy-bearing ternary complexes give abundant M.(+) only for Trp. Density functional theory (DFT) calculations show that for Tyr and Phe, amino-acid displacement reactions by H(2)O and CH(3)OH (giving [Cu(II)(4Cl-tpy)(H(2)O)].(2+) and [Cu(II)(4Cl-tpy)(CH(3)OH)].(2+)) are energetically more favorable than dissociative electron transfer (giving M.(+) and [Cu(I)(4Cl-tpy)](+)). The fragmentation pathway common to all these [Cu(II)(4Cl-tpy)(M)].(2+) ions is the loss of NH(3). DFT calculations show that the loss of NH(3) proceeds via a "phenonium-type" intermediate. Dissociative electron transfer in [Cu(II)(4Cl-tpy)(M-NH(3))].(2+) results in [M-NH(3)].(+). The [Phe-NH(3)] (+) ion dissociates facilely by eliminating CO(2) and giving a metastable phenonium-type ion that rearranges readily into the styrene radical cation.
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Affiliation(s)
- Chi-Kit Siu
- Department of Chemistry and Centre for Research in Mass Spectrometry, York University, 4700 Keele Street, Toronto, Ontario, Canada
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26
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Carnegie PD, Bandyopadhyay B, Duncan MA. Infrared spectroscopy of Cr+(H2O) and Cr2+(H2O): the role of charge in cation hydration. J Phys Chem A 2008; 112:6237-43. [PMID: 18563888 DOI: 10.1021/jp803086v] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Singly and doubly charged chromium-water ion-molecule complexes are produced by laser vaporization in a pulsed-nozzle cluster source. These species are detected and mass-selected in a specially designed time-of-flight mass spectrometer. Vibrational spectroscopy is measured for these complexes in the O-H stretching region using infrared photodissociation spectroscopy and the method of rare gas atom predissociation. Infrared excitation is not able to break the ion-water bonds in these systems, but it leads to elimination of argon, providing an efficient mechanism for detecting the spectrum. The O-H stretches for both singly and doubly charged complexes are shifted to frequencies lower than those for the free water molecule, and the intensity of the symmetric stretch band is strongly enhanced relative to the asymmetric stretch. Partially resolved rotational structure for both complexes shows that the H-O-H bond angle is greater than it is in the free water molecule. These polarization-induced effects are enhanced in the doubly charged ion relative to its singly charged analog.
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Affiliation(s)
- P D Carnegie
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
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27
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Cimas A, Gámez JA, Mó O, Yáñez M, Salpin JY. Computational study on the kinetics of the reaction between Ca2+ and urea. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.03.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Trujillo C, Mó O, Yáñez M, Tortajada J, Salpin JY. Selenourea−Ca2+ Reactions in Gas Phase. Similarities and Dissimilarities with Urea and Thiourea. J Phys Chem B 2008; 112:5479-86. [DOI: 10.1021/jp711927h] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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29
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Tsierkezos NG, Roithová J, Schröder D, Molinou IE, Schwarz H. Solvation of Copper(II) Sulfate in Binary Water/N,N-Dimethylformamide Mixtures: From the Solution to the Gas Phase. J Phys Chem B 2008; 112:4365-71. [DOI: 10.1021/jp710875x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Nikos G. Tsierkezos
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic, Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic, Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64004, 157 10 Zografou, Greece, and Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Jana Roithová
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic, Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic, Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64004, 157 10 Zografou, Greece, and Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic, Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic, Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64004, 157 10 Zografou, Greece, and Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Ioanna E. Molinou
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic, Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic, Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64004, 157 10 Zografou, Greece, and Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Helmut Schwarz
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic, Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic, Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64004, 157 10 Zografou, Greece, and Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
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30
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Yang Z, Rannulu NS, Chu Y, Rodgers MT. Bond Dissociation Energies and Equilibrium Structures of Cu+(MeOH)x, x = 1−6, in the Gas Phase: Competition between Solvation of the Metal Ion and Hydrogen-Bonding Interactions. J Phys Chem A 2008; 112:388-401. [DOI: 10.1021/jp076964v] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Z. Yang
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - N. S. Rannulu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - Y. Chu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - M. T. Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
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31
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Trujillo C, Lamsabhi AM, Mó O, Yáñez M. The importance of the oxidative character of doubly charged metal cations in binding neutral bases. [Urea-M]2+ and [thiourea-M]2+ (M = Mg, Ca, Cu) complexes. Phys Chem Chem Phys 2008; 10:3229-35. [DOI: 10.1039/b802907e] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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32
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Abstract
Studying metal ion solvation, especially hydration, in the gas phase has developed into a field that is dominated by a tight interaction between experiment and theory. Since the studied species carry charge, mass spectrometry is an indispensable tool in all experiments. Whereas gas-phase coordination chemistry and reactions of bare metal ions are reasonably well understood, systems containing a larger number of solvent molecules are still difficult to understand. This review focuses on the rich chemistry of hydrated metal ions in the gas phase, covering coordination chemistry, charge separation in multiply charged systems, as well as intracluster and ion-molecule reactions. Key ideas of metal ion solvation in the gas phase are illustrated with rare-gas solvated metal ions.
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Affiliation(s)
- Martin K Beyer
- Institut für Chemie, Sekr. C4, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany.
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33
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Turecek F. Copper-biomolecule complexes in the gas phase. The ternary way. MASS SPECTROMETRY REVIEWS 2007; 26:563-82. [PMID: 17474124 DOI: 10.1002/mas.20137] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
This review deals with copper complexes of a variety of organic and bioorganic molecules that have been produced as gas-phase ions by electrospray and other ionization methods and studied experimentally by mass spectrometry and theoretically by ab initio and density functional theory computations. Ternary complexes of Cu((II)) allow one to modify the oxidation state and coordination sphere of the copper ion and thus induce novel fragmentations that involve redox and radical-based reactions. Structure elucidation, distinction, and quantitation of leucine and isoleucine isomers in peptides, distinction of enantiomers in chiral compounds, and sensitive detection of antibiotics are some of the highlights of mass spectrometry of ternary copper complexes. Binary copper complexes are mainly represented by Cu((I)) species in which the copper ion displays the properties of a weak Lewis acid.
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Affiliation(s)
- Frantisek Turecek
- Department of Chemistry, Bagley Hall, University of Washington, Seattle, WA 98195-1700, USA.
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34
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Trujillo C, Mó O, Yáñez M, Salpin JY, Tortajada J. Gas-Phase Reactions Between Thiourea and Ca2+: New Evidence for the Formation of [Ca(NH3)]2+ and Other Doubly Charged Species. Chemphyschem 2007; 8:1330-7. [PMID: 17492701 DOI: 10.1002/cphc.200700113] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The gas-phase reactions between Ca(2+) and thiourea are investigated by means of electrospray ionization/mass spectrometry experiments. The MS/MS spectra of [Ca(thiourea)](2+) complexes show the appearance of new doubly charged species formed by the loss of NH(3) and HNCS. Other intense peaks at m/z 43, 56, 60, 73, 76 and 98 are also observed, and assigned to monocations produced in different coulomb-explosion processes. The structures and bonding characteristics of the different stationary points of the [Ca(thiourea)](2+) potential energy surface (PES) were theoretically studied by DFT calculations carried out at B3LYP/cc-pWCVTZ level. The analysis of the topology of this PES permits to propose different mechanisms for the loss of ammonia and HNCS, and to identify, the m/z 43, 56, 60, 73, 76 and 98 peaks as H(2)NCNH(+), CaNH(2) (+), H(2)NCS(+), CaSH(+), thiourea(+) and CaNCS(+) ions respectively. There are significant dissimilarities between the reactivity of urea and thiourea, which are related to the lower ionization energy of the latter, and to the fact that thioenols are intrinsically more stable than enols with respect to the corresponding keto forms.
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Affiliation(s)
- Cristina Trujillo
- Departamento de Química, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
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35
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Duncombe BJ, Duale K, Buchanan-Smith A, Stace AJ. The Solvation of Cu2+ with Gas-Phase Clusters of Water and Ammonia. J Phys Chem A 2007; 111:5158-65. [PMID: 17536792 DOI: 10.1021/jp0717286] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A detailed study has been undertaken of the gas-phase chemistry of [Cu(H2O)N]2+ and [Cu(NH3)N]2+ complexes. Ion intensity distributions and fragmentation pathways (unimolecular and collision-induced) have been recorded for both complexes out as far as N=20. Unimolecular fragmentation is dominated by Coulomb explosion (separation into two single charged units) on the part of the smaller ions, but switches to neutral molecule loss for N>7. In contrast, collisional activation promotes extensive electron capture from the collision gas, with the appearance of particular singly charged fragment ions being sensitive to the size and composition of the precursor. The results show clear evidence of the unit [Cu(X)8]2+ being of special significance, and it is proposed that the hydrogen-bonded structure associated with this ion is responsible for stabilizing the dipositive charge on Cu2+ in aqueous solution.
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Affiliation(s)
- Bridgette J Duncombe
- Department of Physical Chemistry, School of Chemistry, The University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
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36
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Wu J, Liu D, Zhou JG, Hagelberg F, Park SS, Shvartsburg AA. Chemistry in Acetone Complexes of Metal Dications: A Remarkable Ethylene Production Pathway. J Phys Chem A 2007; 111:4748-58. [PMID: 17503788 DOI: 10.1021/jp068574z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electrospray ionization can generate microsolvated multiply charged metal ions for various metals and ligands, allowing exploration of chemistry within such clusters. The finite size of these systems permits comparing experimental results with accurate calculations, creating a natural laboratory to research ion solvation. Mass spectrometry has provided much insight into the stability and dissociation of ligated metal cations. While solvated singly charged ions tend to shrink by ligand evaporation, solvated polycations below a certain size exhibit charge reduction and/or ligand fragmentation due to organometallic reactions. Here we investigate the acetone complexes of representative divalent metals (Ca, Mn, Co, Ni, and Cu), comparing the results of collision-induced dissociation with the predictions of density functional theory. As for other solvated dications, channels involving proton or electron transfer compete with ligand loss and become dominant for smaller complexes. The heterolytic C-C bond cleavage is common, like in DMSO and acetonitrile complexes. Of primary interest is the unanticipated neutral ethylene loss, found for all metals studied except Cu and particularly intense for Ca and Mn. We focus on understanding that process in the context of competing dissociation pathways, as a function of metal identity and number of ligands. According to first-principles modeling, ethylene elimination proceeds along a complex path involving two intermediates. These results suggest that chemistry in microsolvated multiply charged ions may still hold major surprises.
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Affiliation(s)
- Jianhua Wu
- Computational Center for Molecular Structure and Interactions, Department of Physics, Atmospheric Sciences, and Geoscience, Jackson State University, Jackson, Mississippi 39217, USA
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37
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Lamsabhi AM, Alcamí M, Mó O, Yáñez M, Tortajada J, Salpin JY. Unimolecular Reactivity of Uracil–Cu2+ Complexes in the Gas Phase. Chemphyschem 2007; 8:181-7. [PMID: 17154324 DOI: 10.1002/cphc.200600399] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The gas-phase interaction of copper(II) ions with uracil are studied by means of mass spectrometry and B3LYP/6-311+G(2df,2p)//B3LYP/6-31G(d) calculations. Positive-ion electrospray spectra show that the reaction of uracil with copper(II) gives rise to singly charged species, whereby the [Cu(uracil--H)](+) complex is the most intense ion in the spectra at low concentration. Mass spectrometry/mass spectrometry (MS/MS) experiments show that the loss of HNCO and NCO are the dominant fragmentation processes, accompanied by a minor loss of CO. A systematic study of the spectra obtained with different labeled species, namely, 2-(13)C- (m/z 175), 2-(13)C,1,3-(15)N(2)- (m/z 177) and 3-(15)N-uracil (m/z 175), concludes unambiguously that both the loss of HNCO and NCO involve exclusively C2 and N3, whereas only C4 is involved in the loss of CO. Suitable mechanisms for these fragmentation processes are proposed through a theoretical survey of the corresponding potential energy surface. In these mechanisms, pi complexes, which lie high in energy with respect to the global minimum, play a significant role in the loss of NCO; this explains why both products, HNCO and NCO involve the same atoms of the ring.
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Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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38
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Lam CNW, Ruan EDL, Ma CY, Chu IK. Non-zwitterionic structures of aliphatic-only peptides mediated the formation and dissociation of gas phase radical cations. JOURNAL OF MASS SPECTROMETRY : JMS 2006; 41:931-8. [PMID: 16770832 DOI: 10.1002/jms.1052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We have investigated how the non-zwitterionic and zwitterionic structures of aliphatic-only tripeptides affect the formation and dissociation of peptide radical cations in the gas phase. The non-zwitterionic forms of the aliphatic-only peptides in their metal complexes play an important role in determining whether the electron transfer pathway predominates. We extended this study by synthesizing permanent non-zwitterionic and zwitterionic forms of aliphatic-only peptide radical cations and exploring their reactivities in the gas phase. Collision-induced dissociation spectra demonstrated the feasibility of generating both non-zwitterionic and zwitterionic forms. Radical cations in zwitterionic forms may indeed mediate the beta and gamma carbon-carbon bond cleavages of leucine and isoleucine side chains from the GlyGlyXle radical peptides; this feature allows leucine and isoleucine residues to be distinguished unambiguously.
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Affiliation(s)
- Corey N W Lam
- Department of Chemistry, University of Hong Kong, Pokfulam Road, Hong Kong
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39
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Ke Y, Verkerk UH, Shek PYI, Hopkinson AC, Siu KWM. Stable Gas-Phase Radical Cations of Dimeric Tryptophan and Tyrosine Derivatives. J Phys Chem B 2006; 110:8517-23. [PMID: 16623540 DOI: 10.1021/jp060029a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Stable radical cations of dimeric amino acid derivatives of tryptophan and tyrosine were generated by collision-induced dissociation of [Cu(II)(diethylenetriamine)(amino acid derivative)2]*2+. The yields of the dimer radical cations were dependent on both the auxiliary ligand and the tryptophan or tyrosine derivatives used. Amino acid derivatives with an unmodified carboxylic acid group did not generate dimer radical cations. For the amino acid derivatives Ac-Trp-OMe and Ac-Trp-NH2 (Ac is N-acetyl; OMe and NH2 are the methyl ester and amide modifications of the C-terminal carboxylic group), no auxiliary ligand was required for generating the dimer radical cations. Collision-induced dissociation of the [Cu(II)(amino acid derivative)4]*2+ precursor generated the dimer radical cation [(amino acid derivative)2]*+. Stabilizing interactions, most likely involving hydrogen bonding, between the two amino acid derivatives are proposed to account for observation of the dimer radical cations. Dissociation of these ions yields protonated or radical cationic amino acid derivatives; these observations are consistent with the expectation of proton competition between monomeric units, whose proton affinities were calculated using density functional theory.
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Affiliation(s)
- Yuyong Ke
- Department of Chemistry and Centre for Research in Mass Spectrometry, York University, 4700 Keele Street, Toronto, Ontario M3J 1P3, Canada
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40
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Pavelka M, Simanek M, Sponer J, Burda JV. Copper Cation Interactions with Biologically Essential Types of Ligands: A Computational DFT Study. J Phys Chem A 2006; 110:4795-809. [PMID: 16599448 DOI: 10.1021/jp056868z] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This work presents a systematic theoretical study on Cu(I) and Cu(II) cations in variable hydrogen sulfide-aqua-ammine ligand fields. These ligands model the biologically most common environment for Cu ions. Molecular structures of the complexes were optimized at the density functional theory (DFT) level. Subsequent thorough energy analyses revealed the following trends: (i) The ammine complexes are the most stable, followed by those containing the aqua and hydrogen sulfide ligands, which are characterized by similar stabilization energies. (ii) The most preferred Cu(I) coordination number is 2 in ammine or aqua ligand fields. A qualitatively different binding picture was obtained for complexes with H(2)S ligands where the 4-coordination is favored. (iii) The 4- and 5-coordinated structures belong to the most stable complexes for Cu(II), regardless of the ligand types. Vertical and adiabatic ionization potentials of Cu(I) complexes were calculated. Charge distribution (using the natural population analysis (NPA) method) and molecular orbital analyses were performed to elucidate the nature of bonding in the examined systems. The results provide in-depth insight into the Cu-binding properties and can be, among others, used for the calibration of bioinorganic force fields.
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Affiliation(s)
- Matej Pavelka
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
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41
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Walters RS, Pillai ED, Duncan MA. Solvation dynamics in Ni+ (H2O)n clusters probed with infrared spectroscopy. J Am Chem Soc 2006; 127:16599-610. [PMID: 16305249 DOI: 10.1021/ja0542587] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Infrared photodissociation spectroscopy is reported for mass-selected Ni+ (H2O)n complexes in the O-H stretching region up to cluster sizes of n = 25. These clusters fragment by the loss of one or more intact water molecules, and their excitation spectra show distinct bands in the region of the symmetric and asymmetric stretches of water. The first evidence for hydrogen bonding, indicated by a broad band strongly red-shifted from the free OH region, appears at the cluster size of n = 4. At larger cluster sizes, additional red-shifted structure evolves over a broader wavelength range in the hydrogen-bonding region. In the free OH region, the symmetric stretch gradually diminishes in intensity, while the asymmetric stretch develops into a closely spaced doublet near 3700 cm(-1). The data indicate that essentially all of the water molecules are in a hydrogen-bonded network by the size of n = 10. However, there is no evidence for the formation of clathrate structures seen recently via IR spectroscopy of protonated water clusters.
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Affiliation(s)
- Richard S Walters
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
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42
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Stone JA, Su T, Vukomanovic D. A collisionally activated dissociation (CAD) and computational investigation of doubly and singly charged DMSO complexes of Cu2+. CAN J CHEM 2005. [DOI: 10.1139/v05-201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The singly and doubly charged Cu(II)DMSO complexes formed by electrospray have been examined by CAD and computation. The CAD spectra were obtained as a function of collision energy. The doubly charged ions, [Cu(DMSO)n]2+, were observed only for n ≥ 2. For n = 3, dissociation leads mainly to [Cu(DMSO)2]+ + DMSO+, with only a trace of [Cu(DMSO)2]2+. Although [Cu(DMSO)]2+ was never detected, computation shows that the n = 1 complex exists in a potential well. Loss of DMSO+ is computed to be exothermic for n = 13, the exothermicity decreasing as n increases. The singly charged complexes in the ESI spectra were [CuX(DMSO)n]+ (X = Cl, Br, NO3, HSO4, n = 1 or 2). The CAD spectra showed competition between electron transfer from anion to metal followed by loss of X and loss of DMSO+. Experiment and computation show that for [CuX(DMSO)]+, loss of X is the preferred decomposition at low collision energy. NBO analysis shows that electron transfer to Cu from DMSO decreases in [Cu(DMSO)n]2+ as n increases, the bonding becoming more electrostatic and less covalent. In [CuX(DMSO)n]+, the negative charge on X is much less than unity with most of the difference appearing on the DMSO ligand(s).Key words: copperDMSO complexes, electrospray, CAD, structures.
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Palacios A, Corral I, Mó O, Martín F, Yáñez M. On the existence and lifetimes of Cu2+ complexes with water, ammonia, and hydrogen cyanide. J Chem Phys 2005; 123:014315. [PMID: 16035843 DOI: 10.1063/1.1950607] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
High-level ab initio calculations have been carried out to evaluate the lifetimes of complexes formed by the association of Cu2+ to water, ammonia, and hydrogen cyanide. The corresponding binding energies were evaluated at the CCSD(T)6-311+G(3df,2pd) level of theory. The potential-energy curves corresponding to their dissociation into Cu+ + L+ (L=H2O, NH3, and HCN) were obtained at the CCSD(T)6-311+G(3df,2p) level on BHLYP6-311+G(d,p) optimized geometries. Lifetimes were calculated using the exterior complex scaling and the semiclassical WKB methods. Although all the complexes investigated are thermodynamically unstable with respect to their dissociation into Cu+ + L+ in a typical Coulomb explosion, the activation barrier is high enough to accommodate several vibrational resonances, with very large lifetimes. As a matter of fact, if the three complexes are produced in the lowest vibrational levels, they behave as totally bound (with almost infinite lifetime) species.
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Affiliation(s)
- Alicia Palacios
- Departamento de Química, Universidad Autónoma de Madrid, Cantoblanco, C-9 E-28049 Madrid, Spain
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Pavelka M, Burda JV. Theoretical description of copper Cu(I)/Cu(II) complexes in mixed ammine-aqua environment. DFT and ab initio quantum chemical study. Chem Phys 2005. [DOI: 10.1016/j.chemphys.2004.11.034] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Burda JV, Shukla MK, Leszczynski J. Theoretical model of the aqua-copper [Cu(H2O)5]+cation interactions with guanine. J Mol Model 2005; 11:362-9. [PMID: 15928918 DOI: 10.1007/s00894-005-0269-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2004] [Accepted: 01/31/2005] [Indexed: 10/25/2022]
Abstract
Pentaaqua complexes of Cu(I) with guanine were optimized at the DFT B3PW91/6-31G(d) level. For the most stable structures, vibration frequencies and NBO charges were computed followed by energy analyses. The order of individual conformers was very sensitive to the method and basis sets used for the calculation. Several conformers are practically degenerated in energy. The inclusion of an entropy term changes the order of the conformers' stability. Water molecules associated at the N9 position of guanine are favored by the inclusion of the entropy correction. Bonding energies of Cu-O(aqua) interactions were estimated to be about 60 kcal mol(-1) and for Cu-N7 bonding in the range of 75-83 kcal mol(-1). The broad range in Cu-N interaction energies demonstrates the role of induction effects caused by water molecules associated at the various sites of guanine. The charge distribution of the guanine molecule is changed remarkably by the coordination of a Cu(I) cation, which can also change the base-pairing pattern of the guanine.
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Affiliation(s)
- Jaroslav V Burda
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16, Prague 2, Czech Republic.
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Shi T, Zhao J, Hopkinson AC, Siu KWM. Formation of Abundant [Pb(H2O)]2+ by Ligand-Exchange Reaction between [Pb(N2)n]2+ (n = 1−3) and H2O. J Phys Chem B 2005; 109:10590-3. [PMID: 16852285 DOI: 10.1021/jp051174b] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Doubly charged lead monohydrate, [Pb(H2O)]2+, was predicted to be unstable in the gas phase, but it has recently been observed to form in low yield via ligand change between [Pb(CH3CN)]2+ and H2O [Shi, T.; Orlova, G.; Guo, J.; Bohme, D. K.; Hopkinson, A. C.; Siu, K. W. M. J. Am. Chem. Soc. 2004, 126, 7975-7980]. Here we report that abundant [Pb(H2O)]2+ is formed in the gas phase by ligand-exchange reaction between [Pb(N2)n]2+ (n = 1-3) and water after collisional activation. Density functional theory has been used to examine the ligand-exchange reaction profile. A comparison of the potential-energy surfaces between [Pb(N2)]2+ and [Pb(CH3CN)]2+ reacting with H2O provides strong evidence that the ligand-exchange reaction of [Pb(N2)]2+ with H2O to form [Pb(H2O)]2+ is more efficient than that of [Pb(CH3CN)]2+ with H2O.
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Affiliation(s)
- Tujin Shi
- Department of Chemistry and Centre for Research in Mass Spectrometry, York University, 4700 Keele Street, Toronto, Ontario, Canada M3J 1P3
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Chu IK, Lam CNW, Siu SO. Facile generation of tripeptide radical cations in vacuo via intramolecular electron transfer in Cu(II) tripeptide complexes containing sterically encumbered terpyridine ligands. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2005; 16:763-771. [PMID: 15862777 DOI: 10.1016/j.jasms.2005.01.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Revised: 01/27/2005] [Accepted: 01/29/2005] [Indexed: 05/24/2023]
Abstract
Molecular radical cations of tripeptides of the form glycylglycyl(residue X) (GGX*+) are produced by the collision-induced, intramolecular one-electron transfer of [Cu(II)(L)GGX]*2+ complexes (L = triamine ligand). We demonstrate, for the first time, the formation of molecular radical cations of all of the aliphatic, basic, aromatic, acidic, and some heteroatom-bearing GGX tripeptides, albeit inefficiently in some cases, by altering the structure of the auxiliary polyamine ligand bound to the copper atom. The design of the ligand allows exquisite control over the nature of the dissociation pathway. Steric hindrance of bulky groups in the ligand affects the binding of the peptide to the copper ion; this interaction is an important factor in determining whether the electron transfer pathway predominates.
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Affiliation(s)
- Ivan K Chu
- Department of Chemistry, The University of Hong Kong, Hong Kong, SAR China.
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Roithová J, Schröder D, Loos J, Schwarz H, Jankowiak HC, Berger R, Thissen R, Dutuit O. Revision of the second ionization energy of toluene. J Chem Phys 2005; 122:094306. [PMID: 15836127 DOI: 10.1063/1.1856916] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Charge stripping (CS) of the molecular ion of toluene, C(7)H(8) (+)-->C(7)H(8) (2+)+e, is often used as a reference for the determination of second ionization energies in energy-resolved CS experiments. For calibration of the kinetic energy scale, a value of IE(C(7)H(8) (+))=(15.7+/-0.2) eV derived from the appearance energy of the toluene dication upon electron ionization has been accepted generally. Triggered by some recent discrepancies between CS measurements on the one hand and different experimental methods as well as theoretical predictions on the other, we have reinvestigated the photon-induced double ionization of toluene using synchrotron radiation. These photoionization measurements yield phenomenological appearance energies of AE(C(7)H(8) (+))=(8.81+/-0.03) eV for the monocation and AE(C(7)H(8) (2+))=(23.81+/-0.06) eV for the dication. The former is in good agreement with a much more precise spectroscopic value, IE(C(7)H(8))=(8.8276+/-0.0006) eV. Explicit consideration of the Franck-Condon envelopes associated with photoionization to the dication in conjunction with the application of the Wannier law leads to an adiabatic ionization energy IE(a)(C(7)H(8) (+))=(14.8+/-0.1) eV, which is as much as 0.9 eV lower than the previous value derived from electron ionization. Because in many previous CS measurements the transition C(7)H(8) (+)-->C(7)H(8) (2+)+e was used as a reference, the energetics of several gaseous dications might need some readjustment.
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Affiliation(s)
- Jana Roithová
- Institut für Chemie der Technischen Universität Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany
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Ducéré JM, Goursot A, Berthomieu D. Comparative Density Functional Theory Study of the Binding of Ligands to Cu+ and Cu2+: Influence of the Coordination and Oxidation State. J Phys Chem A 2004; 109:400-8. [PMID: 16833359 DOI: 10.1021/jp047971b] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BP86, B3LYP and MP2 methods, generally used to study large systems containing transition metals, were compared for their ability to accuratly evaluate bond dissociation energies of copper complexes. Various [Cu-L]+ and [Cu-L]2+ complexes in which L are small ligands and the higher coordinated complexes, [Cu(NH3)(4)]+ and [Cu(NH3)4]2+ were studied. For monoligated complexes, the BDEs calculated by the three methods differed by 2 to 60 kcal/mol, the larger differences being obtained for [Cu-L]2+ complexes. The BDEs calculated using the B3LYP functional were in general close to the experimental values whereas the BDEs calculated using the BP86 functional were too high and the BDEs calculated using the MP2 were too low. If we rank the whole ligands according to their increased bond strength, the resulting orders obtained with the three methods are different for the [Cu-L]+ complexes, the B3LYP giving the same order as the experimental one. This result indicates that the BDEs of [Cu-L]+ complexes are better modeled using the B3LYP than using the BP86 and MP2 methods. For [Cu-L]2+, B3LYP also gave the most reliable results whereas BP86 gave too large BDEs and MP2 gave too small BDEs. However, symmetries of ground states can be different using DFT and post-Hartree-Fock methods. For [Cu-N2O]2+ the use of the B1LYP provides a better symmetry of the complex than the B3LYP, as has been recently shown in the literature for [Cu-H2O]2+. MP2 led to an incorrect bent structure for [Cu-N2]2+ in contrast to a linear structure obtained with the other methods, including CCSD(T). However, due to the lack of experimental data for [Cu-L]2+ complexes and to contrasted results for the methods, it is not possible to conclude definitely. For the high coordinated complexes [Cu(NH3)4]+ and [Cu(NH3)4]2+, the PBE calculation method was used in addition to the BP86, B3LYP and MP2. The BDE values were very close to each other when there is no change of the oxidation state during the reaction. On the basis of these calculations, the choice of the method was less crucial for high coordinated complexes [Cu(NH3)4]+ and [Cu(NH3)4]2+ so long as the oxidation state remained the same during the reaction. In contrast, when [Cu(NH3)4]2+ is reduced in [Cu(NH3)3]+ and NH3, the BDE calculated using the four methods were markedly different.
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Affiliation(s)
- Jean-Marie Ducéré
- Laboratoire de Matériaux Catalytiques et Catalyse en Chimie Organique, UMR 5618 CNRS-ENSCM-UM1, Institut Gerhardt FR 1878, ENSCM, 8, rue de l'Ecole Normale, 34296 Montpellier Cedex 5, France
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Song JH, Kim J, Seo G, Lee JY. Ab initio study on the structures, energies, and vibrational frequencies of acetone complexes with metal monocations and dications. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2004.08.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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