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Najafpour MM, Abbasi Isaloo M, Abasi M, Hołyńska M. Manganese oxide as a water-oxidizing catalyst: from the bulk to Ångström-scale. NEW J CHEM 2014. [DOI: 10.1039/c3nj01393f] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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52
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Najafpour MM, Abasi M, Hołyńska M. Nanolayered manganese oxides as water-oxidizing catalysts: the effects of Cu(ii) and Ni(ii) ions. RSC Adv 2014. [DOI: 10.1039/c4ra05617e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We synthesized nanolayered manganese oxides in the presence of copper(ii) or nickel(ii) ions, and considered the water oxidizing activities of them.
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Affiliation(s)
- Mohammad Mahdi Najafpour
- Department of Chemistry
- Institute for Advanced Studies in Basic Sciences (IASBS)
- Zanjan, Iran
- Center of Climate Change and Global Warming
- Institute for Advanced Studies in Basic Sciences (IASBS)
| | - Mahnaz Abasi
- Department of Chemistry
- Institute for Advanced Studies in Basic Sciences (IASBS)
- Zanjan, Iran
| | - Małgorzata Hołyńska
- Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften (WZMW)
- Philipps-Universität Marburg
- Marburg, Germany
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53
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Yoshizawa K. Quantum Chemical Studies on Dioxygen Activation and Methane Hydroxylation by Diiron and Dicopper Species as well as Related Metal–Oxo Species. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2013. [DOI: 10.1246/bcsj.20130127] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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54
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Peng DL. Synthesis and crystal structures of Manganese(IV) complexes with tridentate schiff bases. RUSS J COORD CHEM+ 2013. [DOI: 10.1134/s1070328413070087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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55
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Importance of trivalency and the e(g)(1) configuration in the photocatalytic oxidation of water by Mn and Co oxides. Proc Natl Acad Sci U S A 2013; 110:11704-7. [PMID: 23818589 DOI: 10.1073/pnas.1310703110] [Citation(s) in RCA: 143] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Prompted by the early results on the catalytic activity of LiMn2O4 and related oxides in the photochemical oxidation of water, our detailed study of several manganese oxides has shown that trivalency of Mn is an important factor in determining the catalytic activity. Thus, Mn2O3, LaMnO3, and MgMn2O4 are found to be very good catalysts with turnover frequencies of 5 × 10(-4) s(-1), 4.8 × 10(-4) s(-1), and 0.8 × 10(-4) s(-1), respectively. Among the cobalt oxides, Li2Co2O4 and LaCoO3--especially the latter--exhibit excellent catalytic activity, with the turnover frequencies being 9 × 10(-4) s(-1) and 1.4 × 10(-3) s(-1), respectively. The common feature among the catalytic Mn and Co oxides is not only that Mn and Co are in the trivalent state, but Co(3+) in the Co oxides is in the intermediate t2g(5)e(g)(1) state whereas Mn(3+) is in the t2g(3e(g)(1) state. The presence of the e(g)(1) electron in these Mn and Co oxides is considered to play a crucial role in the photocatalytic properties of the oxides.
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56
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Najafpour MM, Amouzadeh Tabrizi M, Haghighi B, Govindjee. A 2-(2-hydroxyphenyl)-1H-benzimidazole-manganese oxide hybrid as a promising structural model for the tyrosine 161/histidine 190-manganese cluster in photosystem II. Dalton Trans 2013. [PMID: 23178300 DOI: 10.1039/c2dt32236f] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this communication, we report the synthesis, characterization, and electrochemistry of a 2-(2-hydroxyphenyl)-1H-benzimidazole-manganese oxide hybrid. Our results suggest that this compound is a promising model for the manganese cluster together with tyrosine-161 and histidine-190 in photosystem II of plants, algae and cyanobacteria.
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Affiliation(s)
- Mohammad Mahdi Najafpour
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan, 45137-66731, Iran.
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57
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58
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Najafpour MM, Kompany-Zareh M, Zahraei A, Jafarian Sedigh D, Jaccard H, Khoshkam M, Britt RD, Casey WH. Mechanism, decomposition pathway and new evidence for self-healing of manganese oxides as efficient water oxidizing catalysts: new insights. Dalton Trans 2013; 42:14603-11. [DOI: 10.1039/c3dt51406d] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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59
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Najafpour MM, Sedigh DJ, Pashaei B, Nayeri S. Water oxidation by nano-layered manganese oxides in the presence of cerium(iv) ammonium nitrate: important factors and a proposed self-repair mechanism. NEW J CHEM 2013. [DOI: 10.1039/c3nj00372h] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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60
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Berg N, Hooper TN, Liu J, Beedle CC, Singh SK, Rajaraman G, Piligkos S, Hill S, Brechin EK, Jones LF. Synthetic, structural, spectroscopic and theoretical study of a Mn(iii)–Cu(ii) dimer containing a Jahn–Teller compressed Mn ion. Dalton Trans 2013; 42:207-16. [DOI: 10.1039/c2dt31995k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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61
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Meally ST, Taylor SM, Brechin EK, Piligkos S, Jones LF. Homo- and heterometallic planes, chains and cubanes. Dalton Trans 2013; 42:10315-25. [DOI: 10.1039/c3dt51131f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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62
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Brena B, Siegbahn PEM, Ågren H. Modeling Near-Edge Fine Structure X-ray Spectra of the Manganese Catalytic Site for Water Oxidation in Photosystem II. J Am Chem Soc 2012; 134:17157-67. [DOI: 10.1021/ja306794p] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Barbara Brena
- Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala, Sweden
| | - Per E. M. Siegbahn
- Department of Physics, Alba
Nova, and Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University, SE-106 91, Stockholm, Sweden
| | - Hans Ågren
- School of Biotechnology, Theoretical
Chemistry and Biology, Royal Institute of Technology, S-106 91 Stockholm, Sweden
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63
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Kondaveeti SK, Vaddypally S, Lam C, Hirai D, Ni N, Cava RJ, Zdilla MJ. Synthesis, Structure, and Magnetic Studies of Manganese–Oxygen Clusters of Reduced Coordination Number, Featuring an Unchelated, 5-Coordinate Octanuclear Manganese Cluster with Water-Derived Oxo Ligands. Inorg Chem 2012; 51:10095-104. [DOI: 10.1021/ic202448c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Sandeep K. Kondaveeti
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia,
Pennsylvania 19122, United States
| | - Shivaiah Vaddypally
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia,
Pennsylvania 19122, United States
| | - Carol Lam
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia,
Pennsylvania 19122, United States
| | - Daigorou Hirai
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544,
United States
| | - Ni Ni
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544,
United States
| | - Robert J. Cava
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544,
United States
| | - Michael J. Zdilla
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia,
Pennsylvania 19122, United States
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64
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Redox systematics of a magma ocean with variable pressure-temperature gradients and composition. Proc Natl Acad Sci U S A 2012; 109:11955-60. [PMID: 22778438 DOI: 10.1073/pnas.1202754109] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Oxygen fugacity in metal-bearing systems controls some fundamental aspects of the geochemistry of the early Earth, such as the FeO and siderophile trace element content of the mantle, volatile species that influence atmospheric composition, and conditions for organic compounds synthesis. Redox and metal-silicate equilibria in the early Earth are sensitive to oxygen fugacity (fO(2)), yet are poorly constrained in modeling and experimentation. High pressure and temperature experimentation and modeling in metal-silicate systems usually employs an approximation approach for estimating fO(2) that is based on the ratio of Fe and FeO [called "ΔIW (ratio)" hereafter]. We present a new approach that utilizes free energy and activity modeling of the equilibrium: Fe + SiO(2) + O(2) = Fe(2)SiO(4) to calculate absolute fO(2) and relative to the iron-wüstite (IW) buffer at pressure and temperature [ΔIW (P,T)]. This equilibrium is considered across a wide range of pressures and temperatures, including up to the liquidus temperature of peridotite (4,000 K at 50 GPa). Application of ΔIW (ratio) to metal-silicate experiments can be three or four orders of magnitude different from ΔIW (P,T) values calculated using free energy and activity modeling. We will also use this approach to consider the variation in oxygen fugacity in a magma ocean scenario for various thermal structures for the early Earth: hot liquidus gradient, 100 °C below the liquidus, hot and cool adiabatic gradients, and a cool subsolidus adiabat. The results are used to assess the effect of increasing P and T, changing silicate composition during accretion, and related to current models for accretion and core formation in the Earth. The fO(2) in a deep magma ocean scenario may become lower relative to the IW buffer at hotter and deeper conditions, which could include metal entrainment scenarios. Therefore, fO(2) may evolve from high to low fO(2) during Earth (and other differentiated bodies) accretion. Any modeling of core formation and metal-silicate equilibrium should take these effects into account.
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65
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Yang F, Lublow M, Orthmann S, Merschjann C, Tyborski T, Rusu M, Kubala S, Thomas A, Arrigo R, Hävecker M, Schedel-Niedrig T. Metal-free photocatalytic graphitic carbon nitride on p-type chalcopyrite as a composite photocathode for light-induced hydrogen evolution. CHEMSUSCHEM 2012; 5:1227-1232. [PMID: 22707459 DOI: 10.1002/cssc.201100691] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Indexed: 06/01/2023]
Abstract
Recently, it has been shown that an abundant material, polymeric carbon nitride, can produce hydrogen from water under visible-light irradiation in the presence of a sacrificial donor. We present herein the preparation and characterization of graphitic carbon nitride (g-C(3)N(4)) films on p-type semiconducting CuGaSe(2) chalcopyrite thin-film substrates by thermal condensation of a dicyandiamide precursor under inert-gas conditions. Structural and surface morphological studies of the carbon nitride films suggest a high porosity of g-C(3)N(4) thin films consisting of a network of nanocrystallites. Photoelectrochemical investigations show light-induced hydrogen evolution upon cathodic polarization for a wide range of proton concentrations in the aqueous electrolyte. Additionally, synchrotron radiation-based photoelectron spectroscopy has been applied to study the surface/near-surface chemical composition of the utilized g-C(3)N(4) film photocathodes. For the first time, it has been shown that g-C(3)N(4) films coated on p-type CuGaSe(2) thin films can be successfully applied as new photoelectrochemical composite photocathodes for light-induced hydrogen evolution.
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Affiliation(s)
- Florent Yang
- Helmholtz-Zentrum Berlin GmbH, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
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66
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Synthesis, characterisation and catalytic activities of manganese(III) complexes of pyridoxal-based ONNO donor tetradenatate ligands. Polyhedron 2012. [DOI: 10.1016/j.poly.2011.10.029] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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67
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Najafpour MM, Pashaei B. Nanoscale manganese oxide within Faujasite zeolite as an efficient and biomimetic water oxidizing catalyst. Dalton Trans 2012; 41:10156-60. [DOI: 10.1039/c2dt30891f] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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68
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Najafpour MM, Sedigh DJ, King'ondu CK, Suib SL. Nano-sized manganese oxide–bovine serum albumin was synthesized and characterized. It is promising and biomimetic catalyst for water oxidation. RSC Adv 2012. [DOI: 10.1039/c2ra21251j] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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69
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Yamanaka S, Kanda K, Saito T, Umena Y, Kawakami K, Shen JR, Kamiya N, Okumura M, Nakamura H, Yamaguchi K. Electronic and Spin Structures of the CaMn4O5(H2O)4 Cluster in OEC of PSII Refined to 1.9Å X-ray Resolution. ADVANCES IN QUANTUM CHEMISTRY 2012. [DOI: 10.1016/b978-0-12-396498-4.00016-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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70
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Najafpour MM, Hillier W, Shamkhali AN, Amini M, Beckmann K, Jagličić Z, Jagodič M, Strauch P, Moghaddam AN, Beretta G, Bagherzadeh M. Synthesis, characterization, DFT studies and catalytic activities of manganese(ii) complex with 1,4-bis(2,2′:6,2′′-terpyridin-4′-yl) benzene. Dalton Trans 2012; 41:12282-8. [DOI: 10.1039/c2dt31544k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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71
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Ma C, Hu M, Chen H, Chen C, Liu Q. A New Family of Homo‐ and Heterometallic Manganese Complexes at High Oxidation States Derived from the Oxidation of Mn
II
with Ce
IV
: Syntheses, Structures, and Magnetic Properties. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100719] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Cheng‐Bing Ma
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China, Fax: +86‐591‐83792395
| | - Ming‐Qiang Hu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China, Fax: +86‐591‐83792395
| | - Hui Chen
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China, Fax: +86‐591‐83792395
| | - Chang‐Neng Chen
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China, Fax: +86‐591‐83792395
| | - Qiu‐Tian Liu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China, Fax: +86‐591‐83792395
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72
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Grundmeier A, Dau H. Structural models of the manganese complex of photosystem II and mechanistic implications. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:88-105. [PMID: 21787743 DOI: 10.1016/j.bbabio.2011.07.004] [Citation(s) in RCA: 191] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 07/06/2011] [Accepted: 07/08/2011] [Indexed: 11/29/2022]
Abstract
Photosynthetic water oxidation and O₂ formation are catalyzed by a Mn₄Ca complex bound to the proteins of photosystem II (PSII). The catalytic site, including the inorganic Mn₄CaO(n)H(x) core and its protein environment, is denoted as oxygen-evolving complex (OEC). Earlier and recent progress in the endeavor to elucidate the structure of the OEC is reviewed, with focus on recent results obtained by (i) X−ray spectroscopy (specifically by EXAFS analyses), and (ii) X-ray diffraction (XRD, protein crystallography). Very recently, an impressive resolution of 1.9Å has been achieved by XRD. Most likely however, all XRD data on the Mn₄CaO(n)H(x) core of the OEC are affected by X-ray induced modifications (radiation damage). Therefore and to address (important) details of the geometric and electronic structure of the OEC, a combined analysis of XRD and XAS data has been approached by several research groups. These efforts are reviewed and extended using an especially comprehensive approach. Taking into account XRD results on the protein environment of the inorganic core of the Mn complex, 12 alternative OEC models are considered and evaluated by quantitative comparison to (i) extended-range EXAFS data, (ii) polarized EXAFS of partially oriented PSII membrane particles, and (iii) polarized EXAFS of PSII crystals. We conclude that there is a class of OEC models that is in good agreement with both the recent crystallographic models and the XAS data. On these grounds, mechanistic implications for the O−O bond formation chemistry are discussed. This article is part of a Special Issue entitled: Photosystem II.
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73
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Rivalta I, Amin M, Luber S, Vassiliev S, Pokhrel R, Umena Y, Kawakami K, Shen JR, Kamiya N, Bruce D, Brudvig GW, Gunner MR, Batista VS. Structural-functional role of chloride in photosystem II. Biochemistry 2011; 50:6312-5. [PMID: 21678923 DOI: 10.1021/bi200685w] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Chloride binding in photosystem II (PSII) is essential for photosynthetic water oxidation. However, the functional roles of chloride and possible binding sites, during oxygen evolution, remain controversial. This paper examines the functions of chloride based on its binding site revealed in the X-ray crystal structure of PSII at 1.9 Å resolution. We find that chloride depletion induces formation of a salt bridge between D2-K317 and D1-D61 that could suppress the transfer of protons to the lumen.
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Affiliation(s)
- Ivan Rivalta
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, USA.
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74
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Chakraborty M, Singh NJ, Mandal PC, Das S, Mukhopadhyay S. Mechanistic studies on the oxidation of ascorbic acid and hydroquinone by a {Mn4O6}4+ core in aqueous media. J Phys Chem A 2011; 115:4882-93. [PMID: 21517065 DOI: 10.1021/jp202690a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Described in this work is the kinetics of oxidation of ascorbic acid and hydroquinone by a tetranuclear Mn(IV) oxidant, [Mn(4)(μ-O)(6)(bipy)(6)](4+) (1(4+), bipy =2,2(/)-bipyridine), in aqueous solution over a wide pH range 1.5-6.0. In particular, below pH 3.0, protonation on the oxo-bridge of 1(4+) results in the formation of [Mn(4)(μ-O)(5)(μ-OH)(bipy)(6)](5+) (1H(5+)) as an additional oxidant over 1(4+). Both ascorbic acid and ascorbate whereas only hydroquinone and none of its protolytic species were found to be reactive reducing agents in these reactions. Analysis of the rate data clearly established that the oxo-bridge protonated oxidant 1H(5+) is kinetically far more superior to 1(4+) in oxidizing ascorbic acid and hydroquinone. Rates of these reactions are substantially lowered in D(2)O-enriched media in comparison to that in H(2)O media. An initial one electron one proton transfer electroprotic rate step could be mechanistically conceived. DFT studies established that among the two sets of terminal and central Mn(IV) atoms in the tetranuclear oxidant, one of the two terminal Mn(IV) is reduced to Mn(III) at the rate step that we can intuitively predict considering the probable positive charge distribution on the Mn(IV) atoms.
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75
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Kanda K, Yamanaka S, Saito T, Umena Y, Kawakami K, Shen JR, Kamiya N, Okumura M, Nakamura H, Yamaguchi K. Labile electronic and spin states of the CaMn4O5 cluster in the PSII system refined to the 1.9 Å X-ray resolution. UB3LYP computational results. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.02.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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76
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Cox N, Rapatskiy L, Su JH, Pantazis DA, Sugiura M, Kulik L, Dorlet P, Rutherford AW, Neese F, Boussac A, Lubitz W, Messinger J. Effect of Ca2+/Sr2+ substitution on the electronic structure of the oxygen-evolving complex of photosystem II: a combined multifrequency EPR, 55Mn-ENDOR, and DFT study of the S2 state. J Am Chem Soc 2011; 133:3635-48. [PMID: 21341708 DOI: 10.1021/ja110145v] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electronic structures of the native Mn(4)O(x)Ca cluster and the biosynthetically substituted Mn(4)O(x)Sr cluster of the oxygen evolving complex (OEC) of photosystem II (PSII) core complexes isolated from Thermosynechococcus elongatus, poised in the S(2) state, were studied by X- and Q-band CW-EPR and by pulsed Q-band (55)Mn-ENDOR spectroscopy. Both wild type and tyrosine D less mutants grown photoautotrophically in either CaCl(2) or SrCl(2) containing media were measured. The obtained CW-EPR spectra of the S(2) state displayed the characteristic, clearly noticeable differences in the hyperfine pattern of the multiline EPR signal [Boussac et al. J. Biol. Chem.2004, 279, 22809-22819]. In sharp contrast, the manganese ((55)Mn) ENDOR spectra of the Ca and Sr forms of the OEC were remarkably similar. Multifrequency simulations of the X- and Q-band CW-EPR and (55)Mn-pulsed ENDOR spectra using the Spin Hamiltonian formalism were performed to investigate this surprising result. It is shown that (i) all four manganese ions contribute to the (55)Mn-ENDOR spectra; (ii) only small changes are seen in the fitted isotropic hyperfine values for the Ca(2+) and Sr(2+) containing OEC, suggesting that there is no change in the overall spin distribution (electronic coupling scheme) upon Ca(2+)/Sr(2+) substitution; (iii) the changes in the CW-EPR hyperfine pattern can be explained by a small decrease in the anisotropy of at least two hyperfine tensors. It is proposed that modifications at the Ca(2+) site may modulate the fine structure tensor of the Mn(III) ion. DFT calculations support the above conclusions. Our data analysis also provides strong support for the notion that in the S(2) state the coordination of the Mn(III) ion is square-pyramidal (5-coordinate) or octahedral (6-coordinate) with tetragonal elongation. In addition, it is shown that only one of the currently published OEC models, the Siegbahn structure [Siegbahn, P. E. M. Acc. Chem. Res.2009, 42, 1871-1880, Pantazis, D. A. et al. Phys. Chem. Chem. Phys.2009, 11, 6788-6798], is consistent with all data presented here. These results provide important information for the structure of the OEC and the water-splitting mechanism. In particular, the 5-coordinate Mn(III) is a potential site for substrate 'water' (H(2)O, OH(-)) binding. Its location within the cuboidal structural unit, as opposed to the external 'dangler' position, may have important consequences for the mechanism of O-O bond formation.
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Affiliation(s)
- Nicholas Cox
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany.
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77
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78
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Lassalle-Kaiser B, Hureau C, Pantazis DA, Pushkar Y, Guillot R, Yachandra VK, Yano J, Neese F, Anxolabéhère-Mallart E. Activation of a water molecule using a mononuclear Mn complex: from Mn-aquo, to Mn-hydroxo, to Mn-oxyl via charge compensation. ENERGY & ENVIRONMENTAL SCIENCE 2010; 3:924-938. [PMID: 24772190 PMCID: PMC3997265 DOI: 10.1039/b926990h] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Activation of a water molecule by the electrochemical oxidation of a Mn-aquo complex accompanied by the loss of protons is reported. The sequential (2 × 1 electron/1 proton) and direct (2 electron/2 proton) proton-coupled electrochemical oxidation of a non-porphyrinic six-coordinated Mn(II)OH2 complex into a mononuclear Mn(O) complex is described. The intermediate Mn(III)OH2 and Mn(III)OH complexes are electrochemically prepared and analysed. Complete deprotonation of the coordinated water molecule in the Mn(O) complex is confirmed by electrochemical data while the analysis of EXAFS data reveals a gradual shortening of an Mn-O bond upon oxidation from Mn(II)OH2 to Mn(III)OH and Mn(O). Reactivity experiments, DFT calculations and XANES pre-edge features provide strong evidence that the bonding in Mn(O) is best characterized by a Mn(III)-oxyl description. Such oxyl species could play a crucial role in natural and artificial water splitting reactions. We provide here a synthetic example for such species, obtained by electrochemical activation of a water ligand.
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Affiliation(s)
- Benedikt Lassalle-Kaiser
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), UMR–CNRS 8182, Univ Paris Sud 11, F-91405 Orsay, France
| | - Christelle Hureau
- CNRS, LCC (Laboratoire de Chimie de Coordination), 205 Route de Narbonne, 31077 Toulouse, France, Université de Toulouse, UPS, INPT, LCC, 31077 Toulouse, France. ; Fax: +33(0)5 61 33 30 03; Tel: +33(0)5 61 33 31 20
| | - Dimitrios A. Pantazis
- Institute for Physical and Theoretical Chemistry, University of Bonn, Wegelerstrasse 12, D-53115 Bonn, Germany, Max-Planck Institute for Bioinorganic Chemistry, Stiftstr.32-34, D-45470 Mulheim an der Ruhr, Germany
| | - Yulia Pushkar
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, USA
| | - Régis Guillot
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), UMR–CNRS 8182, Univ Paris Sud 11, F-91405 Orsay, France. ; Fax: +33 5(0)169 15 47 54; Tel: + 33(0)1 69 15 47 52
| | - Vittal K. Yachandra
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, USA
| | - Junko Yano
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, USA
| | - Frank Neese
- Institute for Physical and Theoretical Chemistry, University of Bonn, Wegelerstrasse 12, D-53115 Bonn, Germany, Max-Planck Institute for Bioinorganic Chemistry, Stiftstr.32-34, D-45470 Mulheim an der Ruhr, Germany
| | - Elodie Anxolabéhère-Mallart
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), UMR–CNRS 8182, Univ Paris Sud 11, F-91405 Orsay, France
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79
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Dau H, Limberg C, Reier T, Risch M, Roggan S, Strasser P. The Mechanism of Water Oxidation: From Electrolysis via Homogeneous to Biological Catalysis. ChemCatChem 2010. [DOI: 10.1002/cctc.201000126] [Citation(s) in RCA: 1320] [Impact Index Per Article: 94.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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80
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Dittmer J, Dan H. On the influence of multiple scattering contributions to the extended X-ray absorption fine structure (EXAFS) spectra of the photosystem II manganese complex. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19961001211] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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81
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Liebisch P, Dau H. Linear Dichroism in the XANES of Partially Oriented Samples: Theory and Application to the Photosynthetic Manganese Complex. Chemphyschem 2010; 11:1236-47. [DOI: 10.1002/cphc.200900954] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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82
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Su JH, Messinger J. Is Mn-Bound Substrate Water Protonated in the S(2) State of Photosystem II? APPLIED MAGNETIC RESONANCE 2010; 37:123-136. [PMID: 19960065 PMCID: PMC2784071 DOI: 10.1007/s00723-009-0051-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 06/23/2009] [Indexed: 05/28/2023]
Abstract
In spite of great progress in resolving the geometric structure of the water-splitting Mn(4)O(x)Ca cluster in photosystem II, the binding sites and modes of the two substrate water molecules are still insufficiently characterized. While time-resolved membrane-inlet mass spectrometry measurements indicate that both substrate water molecules are bound to the oxygen-evolving complex (OEC) in the S(2) and S(3) states (Hendry and Wydrzynski in Biochemistry 41:13328-13334, 2002), it is not known (1) if they are both Mn-bound, (2) if they are terminal or bridging ligands, and (3) in what protonation state they are bound in the different oxidation states S(i) (i = 0, 1, 2, 3, 4) of the OEC. By employing (17)O hyperfine sublevel correlation (HYSCORE) spectroscopy we recently demonstrated that in the S(2) state there is only one (type of) Mn-bound oxygen that is water exchangeable. We therefore tentatively identified this oxygen as one substrate 'water' molecule, and on the basis of the finding that it has a hyperfine interaction of about 10 MHz with the electron spin of the Mn(4)O(x)Ca cluster, we suggest that it is bound as a Mn-O-Mn bridge within a bis-mu(2) oxo-bridged unit (Su et al. in J Am Chem Soc 130:786-787, 2008). Employing pulse electron paramagnetic resonance, (1)H/(2)H Mims electron-nuclear double resonance and (2)H-HYSCORE spectroscopies together with (1)H/(2)H-exchange here, we test this hypothesis by probing the protonation state of this exchangeable oxygen. We conclude that this oxygen is fully deprotonated. This result is discussed in the light of earlier reports in the literature.
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Affiliation(s)
- Ji-Hu Su
- Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, Germany
| | - Johannes Messinger
- Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, Germany
- Department of Chemistry, Chemical Biological Center (KBC), Umeå University, 90187 Umeå, Sweden
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83
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Wang X, Maeda K, Thomas A, Takanabe K, Xin G, Carlsson JM, Domen K, Antonietti M. A metal-free polymeric photocatalyst for hydrogen production from water under visible light. NATURE MATERIALS 2009; 8:76-80. [PMID: 18997776 DOI: 10.1038/nmat2317] [Citation(s) in RCA: 5077] [Impact Index Per Article: 338.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Accepted: 10/08/2008] [Indexed: 05/17/2023]
Abstract
The production of hydrogen from water using a catalyst and solar energy is an ideal future energy source, independent of fossil reserves. For an economical use of water and solar energy, catalysts that are sufficiently efficient, stable, inexpensive and capable of harvesting light are required. Here, we show that an abundant material, polymeric carbon nitride, can produce hydrogen from water under visible-light irradiation in the presence of a sacrificial donor. Contrary to other conducting polymer semiconductors, carbon nitride is chemically and thermally stable and does not rely on complicated device manufacturing. The results represent an important first step towards photosynthesis in general where artificial conjugated polymer semiconductors can be used as energy transducers.
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Affiliation(s)
- Xinchen Wang
- Max-Planck Institute of Colloids and Interfaces, Department of Colloid Chemistry, Research Campus Golm, 14424 Postdam, Germany.
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84
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Kuhlman KR, Venkat P, La Duc MT, Kuhlman GM, McKay CP. Evidence of a microbial community associated with rock varnish at Yungay, Atacama Desert, Chile. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jg000677] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Parth Venkat
- California Institute of Technology; Pasadena California USA
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85
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Sproviero EM, McEvoy JP, Gascón JA, Brudvig GW, Batista VS. Computational insights into the O2-evolving complex of photosystem II. PHOTOSYNTHESIS RESEARCH 2008; 97:91-114. [PMID: 18483777 PMCID: PMC2728911 DOI: 10.1007/s11120-008-9307-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2007] [Accepted: 04/10/2008] [Indexed: 05/04/2023]
Abstract
Mechanistic investigations of the water-splitting reaction of the oxygen-evolving complex (OEC) of photosystem II (PSII) are fundamentally informed by structural studies. Many physical techniques have provided important insights into the OEC structure and function, including X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) spectroscopy as well as mass spectrometry (MS), electron paramagnetic resonance (EPR) spectroscopy, and Fourier transform infrared spectroscopy applied in conjunction with mutagenesis studies. However, experimental studies have yet to yield consensus as to the exact configuration of the catalytic metal cluster and its ligation scheme. Computational modeling studies, including density functional (DFT) theory combined with quantum mechanics/molecular mechanics (QM/MM) hybrid methods for explicitly including the influence of the surrounding protein, have proposed chemically satisfactory models of the fully ligated OEC within PSII that are maximally consistent with experimental results. The inorganic core of these models is similar to the crystallographic model upon which they were based, but comprises important modifications due to structural refinement, hydration, and proteinaceous ligation which improve agreement with a wide range of experimental data. The computational models are useful for rationalizing spectroscopic and crystallographic results and for building a complete structure-based mechanism of water-splitting in PSII as described by the intermediate oxidation states of the OEC. This review summarizes these recent advances in QM/MM modeling of PSII within the context of recent experimental studies.
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86
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Pecoraro VL, Hsieh WY. In search of elusive high-valent manganese species that evaluate mechanisms of photosynthetic water oxidation. Inorg Chem 2008; 47:1765-78. [PMID: 18330968 DOI: 10.1021/ic7017488] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Significant progress in the understanding of biological water oxidation has occurred during the past 25 years. Today we have a somewhat clearer description of the structure of the Mn4Ca cluster and an idea of the appropriate oxidation states for the enzyme during catalysis. At issue is the mechanism of water oxidation. Depending on one's belief of the manganese ion oxidation levels at the catalytically active S4 configuration, one can invoke a variety of different processes that could lead to water oxidation. We have suggested that the most likely process is the nucleophilic attack of a water bound to calcium (or manganese) onto a highly electrophilic Mn(V)=O center. In this Article, we explore the difficulties of preparing Mn(V) in dimeric systems and the even more arduous task of definitively assigning oxidation states to such highly reactive species.
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Affiliation(s)
- Vincent L Pecoraro
- Department of Chemistry and Biophysics, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
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87
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Meelich K, Zaleski CM, Pecoraro VL. Using small molecule complexes to elucidate features of photosynthetic water oxidation. Philos Trans R Soc Lond B Biol Sci 2008; 363:1271-9; discussion 1279-81. [PMID: 17954438 DOI: 10.1098/rstb.2007.2224] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The molecular oxygen produced in photosynthesis is generated via water oxidation at a manganese-calcium cluster called the oxygen-evolving complex (OEC). While studies in biophysics, biochemistry, and structural and molecular biology are well known to provide deeper insight into the structure and workings of this system, it is often less appreciated that biomimetic modelling provides the foundation for interpreting photosynthetic reactions. The synthesis and characterization of small model complexes, which either mimic structural features of the OEC or are capable of providing insight into the mechanism of O2 evolution, have become a vital contributor to this scientific field. Our group has contributed to these findings in recent years through synthesis of model complexes, spectroscopic characterization of these systems and probing the reactivity in the context of water oxidation. In this article we describe how models have made significant contributions ranging from understanding the structure of the water-oxidation centre (e.g. contributions to defining a tetrameric Mn3Ca-cluster with a dangler Mn) to the ability to discriminate between different mechanistic proposals (e.g. showing that the Babcock scheme for water oxidation is unlikely).
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Affiliation(s)
- Kristof Meelich
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
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88
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Sproviero EM, Shinopoulos K, Gascón JA, McEvoy JP, Brudvig GW, Batista VS. QM/MM computational studies of substrate water binding to the oxygen-evolving centre of photosystem II. Philos Trans R Soc Lond B Biol Sci 2008; 363:1149-56; discussion 1156. [PMID: 17971333 DOI: 10.1098/rstb.2007.2210] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This paper reports computational studies of substrate water binding to the oxygen-evolving centre (OEC) of photosystem II (PSII), completely ligated by amino acid residues, water, hydroxide and chloride. The calculations are based on quantum mechanics/molecular mechanics hybrid models of the OEC of PSII, recently developed in conjunction with the X-ray crystal structure of PSII from the cyanobacterium Thermosynechococcus elongatus. The model OEC involves a cuboidal Mn3CaO4Mn metal cluster with three closely associated manganese ions linked to a single mu4-oxo-ligated Mn ion, often called the 'dangling manganese'. Two water molecules bound to calcium and the dangling manganese are postulated to be substrate molecules, responsible for dioxygen formation. It is found that the energy barriers for the Mn(4)-bound water agree nicely with those of model complexes. However, the barriers for Ca-bound waters are substantially larger. Water binding is not simply correlated to the formal oxidation states of the metal centres but rather to their corresponding electrostatic potential atomic charges as modulated by charge-transfer interactions. The calculations of structural rearrangements during water exchange provide support for the experimental finding that the exchange rates with bulk 18 O-labelled water should be smaller for water molecules coordinated to calcium than for water molecules attached to the dangling manganese. The models also predict that the S1-->S2 transition should produce opposite effects on the two water-exchange rates.
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Affiliation(s)
- Eduardo M Sproviero
- Department of Chemistry, Yale University, PO Box 208107, New Haven, CT 06520-8107, USA
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89
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Zein S, Kulik LV, Yano J, Kern J, Pushkar Y, Zouni A, Yachandra VK, Lubitz W, Neese F, Messinger J. Focusing the view on nature's water-splitting catalyst. Philos Trans R Soc Lond B Biol Sci 2008; 363:1167-77; discussion 1177. [PMID: 17989003 DOI: 10.1098/rstb.2007.2212] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Nature invented a catalyst about 3Gyr ago, which splits water with high efficiency into molecular oxygen and hydrogen equivalents (protons and electrons). This reaction is energetically driven by sunlight and the active centre contains relatively cheap and abundant metals: manganese and calcium. This biological system therefore forms the paradigm for all man-made attempts for direct solar fuel production, and several studies are underway to determine the electronic and geometric structures of this catalyst. In this report we briefly summarize the problems and the current status of these efforts and propose a density functional theory-based strategy for obtaining a reliable high-resolution structure of this unique catalyst that includes both the inorganic core and the first ligand sphere.
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Affiliation(s)
- Samir Zein
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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90
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Pérez LM, Webster CE, Low AA, Hall MB. Theoretical study of the biologically important dioxo diiron diamond core structures. Theor Chem Acc 2008. [DOI: 10.1007/s00214-008-0438-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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91
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Yano J, Yachandra VK. Where water is oxidized to dioxygen: structure of the photosynthetic Mn4Ca cluster from X-ray spectroscopy. Inorg Chem 2008; 47:1711-26. [PMID: 18330965 PMCID: PMC3947645 DOI: 10.1021/ic7016837] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Light-driven oxidation of water to dioxygen in plants, algae, and cyanobacteria is catalyzed within photosystem II (PS II) by a Mn 4Ca cluster. Although the cluster has been studied by many different methods, its structure and mechanism have remained elusive. X-ray absorption and emission spectroscopy and extended X-ray absorption fine structure studies have been particularly useful in probing the electronic and geometric structures and the mechanism of the water oxidation reaction. Recent progress, reviewed here, includes polarized X-ray absorption spectroscopy measurements of PS II single crystals. Analysis of those results has constrained the Mn 4Ca cluster geometry to a set of three similar high-resolution structures. The structure of the cluster from the present study is unlike either the 3.0- or 3.5-A-resolution X-ray structures or other previously proposed models. The differences between the models derived from X-ray spectroscopy and crystallography are predominantly because of damage to the Mn 4Ca cluster by X-rays under conditions used for the structure determination by X-ray crystallography. X-ray spectroscopy studies are also used for studying the changes in the structure of the Mn 4Ca catalytic center as it cycles through the five intermediate states known as the S i states ( i = 0-4). The electronic structure of the Mn 4Ca cluster has been studied more recently using resonant inelastic X-ray scattering spectroscopy (RIXS), in addition to the earlier X-ray absorption and emission spectroscopy methods. These studies are revealing that the assignment of formal oxidation states is overly simplistic. A more accurate description should consider the charge density on the Mn atoms, which includes the covalency of the bonds and delocalization of the charge over the cluster. The geometric and electronic structures of the Mn 4Ca cluster in the S states derived from X-ray spectroscopy are leading to a detailed understanding of the mechanism of O-O bond formation during the photosynthetic water-splitting process.
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Affiliation(s)
- Junko Yano
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Vittal K. Yachandra
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
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92
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Feng PL, Beedle CC, Koo C, Wernsdorfer W, Nakano M, Hill S, Hendrickson DN. Heterometallic Integer-Spin Analogues of S = 9/2 Mn4 Cubane Single-Molecule Magnets. Inorg Chem 2008; 47:3188-204. [DOI: 10.1021/ic702241m] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Patrick L. Feng
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
| | - Christopher C. Beedle
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
| | - Changhyun Koo
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
| | - Wolfgang Wernsdorfer
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
| | - Motohiro Nakano
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
| | - Stephen Hill
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
| | - David N. Hendrickson
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, Institut Néel, CNRS, BP166, Grenoble Cedex 9, France, Department of Physics, University of Florida, Gainesville, Florida 32611, and Division of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan
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93
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Sproviero EM, Gascón JA, McEvoy JP, Brudvig GW, Batista VS. Quantum Mechanics/Molecular Mechanics Study of the Catalytic Cycle of Water Splitting in Photosystem II. J Am Chem Soc 2008; 130:3428-42. [DOI: 10.1021/ja076130q] [Citation(s) in RCA: 311] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eduardo M. Sproviero
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107
| | - José A. Gascón
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107
| | - James P. McEvoy
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107
| | - Victor S. Batista
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107
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94
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Computational studies of the O(2)-evolving complex of photosystem II and biomimetic oxomanganese complexes. Coord Chem Rev 2008; 252:395-415. [PMID: 19190716 DOI: 10.1016/j.ccr.2007.09.006] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In recent years, there has been considerable interest in studies of catalytic metal clusters in metalloproteins based on Density Functional Theory (DFT) quantum mechanics/molecular mechanics (QM/MM) hybrid methods. These methods explicitly include the perturbational influence of the surrounding protein environment on the structural/functional properties of the catalytic centers. In conjunction with recent breakthroughs in X-ray crystallography and advances in spectroscopic and biophysical studies, computational chemists are trying to understand the structural and mechanistic properties of the oxygen-evolving complex (OEC) embedded in photosystem II (PSII). Recent studies include the development of DFT-QM/MM computational models of the Mn(4)Ca cluster, responsible for photosynthetic water oxidation, and comparative quantum mechanical studies of biomimetic oxomanganese complexes. A number of computational models, varying in oxidation and protonation states and ligation of the catalytic center by amino acid residues, water, hydroxide and chloride have been characterized along the PSII catalytic cycle of water splitting. The resulting QM/MM models are consistent with available mechanistic data, Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction data and extended X-ray absorption fine structure (EXAFS) measurements. Here, we review these computational efforts focused towards understanding the catalytic mechanism of water oxidation at the detailed molecular level.
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95
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Mullins CS, Pecoraro VL. Reflections on Small Molecule Manganese Models that Seek to Mimic Photosynthetic Water Oxidation Chemistry. Coord Chem Rev 2008; 252:416-443. [PMID: 19081816 PMCID: PMC2597837 DOI: 10.1016/j.ccr.2007.07.021] [Citation(s) in RCA: 311] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Recent advances in the study of the Oxygen Evolving Complex (OEC) of Photosystem II (PSII) include structural information attained from several X-ray crystallographic (XRD) and spectroscopic (XANES and EXAFS) investigations. The possible structural features gleaned from these studies have enabled synthetic chemists to design more accurate model complexes, which in turn, offer better insight into the possible pathways used by PSII to drive photosynthetic water oxidation catalysis. Mononuclear model compounds have been used to advance the knowledge base regarding the physical properties and reactivity of high-valent (Mn(IV) or Mn(V)) complexes. Such investigations have been especially important in regard to the manganyl (Mn(IV)=O or Mn(V)≡O) species, as there are no reports, to date, of any structural characterized multinuclear model compounds that incorporate such a functionality. Dinuclear and trinuclear model compounds have also been thoroughly studied in attempts to draw further comparison to the physical properties observed in the natural system and to design systems of catalytic relevance. As the reactive center of the OEC has been shown to contain an oxo-Mn(4)Ca cluster, exact structural models necessitate a tetranuclear Mn core. The number of models that make use of Mn(4) clusters has risen substantially in recent years, and these models have provided evidence to support and refute certain mechanistic proposals. Further work is needed to adequately address the rationale for Ca (and Cl) in the OEC and to determine the sequence of events that lead to O(2) evolution.
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Affiliation(s)
- Christopher S Mullins
- Department of Chemistry, The University of Michigan, 930 North University Avenue, Ann Arbor, MI 48109-1055, USA
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96
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The incorporation of Me-histidine complexes in the structure of FAU-type zeolite: Characterization of the obtained materials. HEMIJSKA INDUSTRIJA 2008. [DOI: 10.2298/hemind0803125s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
L-histidine, a naturally occurring amino acid, was incorporated inside the supercages of FAU type zeolite in a form of Me-complex entity (Me = Cu(II), Zn(II), Fe(III)). The preparation was done either by ion-exchange procedure, or previously prepared Me-histidine complex was incorporated into the a cages of Y zeolite by occlusion. The preparation procedure was found to be a very important factor, as well as the amount of metal complex loaded on the zeolite. The characterization of obtained samples was performed using Diffuse Reflectance Ultraviolet-Visible Spectroscopy (DRUV-Vis), 13C MAS NMR and Infrared Spectroscopy (FTIR). It was noticed that 1-hostidine interacted with the zeolitic framework, and with the extra-framework cation, as well. The results obtained by TG-DSC/MAS technique, revealed that the thermal stability of incorporated histidine was increased, in comparison with that one of pure histidine.
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97
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de Boer JW, Alsters PL, Meetsma A, Hage R, Browne WR, Feringa BL. The role of salicylic acid, l-ascorbic acid and oxalic acid in promoting the oxidation of alkenes with H2O2 catalysed by [MnIV2(O)3(tmtacn)2]2+. Dalton Trans 2008:6283-95. [DOI: 10.1039/b809177c] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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98
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Shevela D, Klimov V, Messinger J. Interactions of photosystem II with bicarbonate, formate and acetate. PHOTOSYNTHESIS RESEARCH 2007; 94:247-64. [PMID: 17653834 DOI: 10.1007/s11120-007-9200-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Accepted: 05/16/2007] [Indexed: 05/16/2023]
Abstract
In this study, we probe the effects of bicarbonate (hydrogencarbonate), BC, removal from photosystem II in spinach thylakoids by measuring flash-induced oxygen evolution patterns (FIOPs) with a Joliot-type electrode. For this we compared three commonly employed methods: (1) washing in BC-free medium, (2) formate addition, and (3) acetate addition. Washing of the samples with buffers depleted of BC and CO2 by bubbling with argon (Method 1) under our conditions leads to an increase in the double hit parameter of the first flash (beta 1), while the miss parameter and the overall activity remain unchanged. In contrast, addition of 40-50 mM formate or acetate results in a significant increase in the miss parameter and to an approximately 50% (formate) and approximately 10% (acetate) inhibition of the overall oxygen evolution activity, but not to an increased beta 1 parameter. All described effects could be reversed by washing with formate/acetate free buffer and/or addition of 2-10 mM bicarbonate. The redox potential of the water-oxidizing complex (WOC) in samples treated by Method 1 is compared to samples containing 2 mM bicarbonate in two ways: (1) The lifetimes of the S0, S2, and S3 states were measured, and no differences were found between the two sample types. (2) The S1, S0, S(-1), and S(-2) states were probed by incubation with small concentrations of NH2OH. These experiments displayed a subtle, yet highly reproducible difference in the apparent Si/S(-i) state distribution which is shown to arise from the interaction of BC with PSII in the already reduced states of the WOC. These data are discussed in detail by also taking into account the CO2 concentrations present in the buffers after argon bubbling and during the measurements. These values were measured by membrane-inlet mass spectrometry (MIMS).
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Affiliation(s)
- Dmitriy Shevela
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
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Kulik LV, Epel B, Lubitz W, Messinger J. Electronic structure of the Mn4OxCa cluster in the S0 and S2 states of the oxygen-evolving complex of photosystem II based on pulse 55Mn-ENDOR and EPR spectroscopy. J Am Chem Soc 2007; 129:13421-35. [PMID: 17927172 DOI: 10.1021/ja071487f] [Citation(s) in RCA: 178] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The heart of the oxygen-evolving complex (OEC) of photosystem II is a Mn4OxCa cluster that cycles through five different oxidation states (S0 to S4) during the light-driven water-splitting reaction cycle. In this study we interpret the recently obtained 55Mn hyperfine coupling constants of the S0 and S2 states of the OEC [Kulik et al. J. Am. Chem. Soc. 2005, 127, 2392-2393] on the basis of Y-shaped spin-coupling schemes with up to four nonzero exchange coupling constants, J. This analysis rules out the presence of one or more Mn(II) ions in S0 in methanol (3%) containing samples and thereby establishes that the oxidation states of the manganese ions in S0 and S2 are, at 4 K, Mn4(III, III, III, IV) and Mn4(III, IV, IV, IV), respectively. By applying a "structure filter" that is based on the recently reported single-crystal EXAFS data on the Mn4OxCa cluster [Yano et al. Science 2006, 314, 821-825] we (i) show that this new structural model is fully consistent with EPR and 55Mn-ENDOR data, (ii) assign the Mn oxidation states to the individual Mn ions, and (iii) propose that the known shortening of one 2.85 A Mn-Mn distance in S0 to 2.75 A in S1 [Robblee et al. J. Am. Chem. Soc. 2002, 124, 7459-7471] corresponds to a deprotonation of a mu-hydroxo bridge between MnA and MnB, i.e., between the outer Mn and its neighboring Mn of the mu3-oxo bridged moiety of the cluster. We summarize our results in a molecular model for the S0 --> S1 and S1 --> S2 transitions.
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Affiliation(s)
- Leonid V Kulik
- Max Planck Institute for Bioinorganic Chemistry, Stiftstrasse 34-36, Mülheim an der Ruhr, Germany.
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Boudalis AK, Aston RE, Smith SJ, Mirams RE, Riley MJ, Schenk G, Blackman AG, Hanton LR, Gahan LR. Synthesis and characterization of the tetranuclear iron(III) complex of a new asymmetric multidentate ligand. A structural model for purple acid phosphatases. Dalton Trans 2007:5132-9. [PMID: 17985020 DOI: 10.1039/b709293h] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ligand, 2-((2-hydroxy-5-methyl-3-((pyridin-2-ylmethylamino)methyl)benzyl)(2-hydroxybenzyl)amino)acetic acid (H(3)HPBA), which contains a donor atom set that mimics that of the active site of purple acid phosphatase is described. Reaction of H(3)HPBA with iron(III) or iron(II) salts results in formation of the tetranuclear complex, [Fe(4)(HPBA)(2)(OAc)(2)(mu-O)(mu-OH)(OH(2))(2)]ClO(4) x 5H(2)O. X-Ray structural analysis reveals the cation consists of four iron(III) ions, two HPBA(3-) ligands, two bridging acetate ligands, a bridging oxide ion and a bridging hydroxide ion. Each binucleating HPBA(3-) ligand coordinates two structurally distinct hexacoordinate iron(III) ions. The two metal ions coordinated to a HPBA(3-) ligand are linked to the two iron(III) metal ions of a second, similar binuclear unit by intramolecular oxide and hydroxide bridging moieties to form a tetramer. The complex has been further characterised by elemental analysis, mass spectrometry, UV-vis and MCD spectroscopy, X-ray crystallography, magnetic susceptibility measurements and variable-temperature Mössbauer spectroscopy.
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Affiliation(s)
- Athanassios K Boudalis
- Institute of Materials Science, NCSR "Demokritos", 15310 Aghia Paraskevi Attikis, Greece
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