1
|
Drosou M, Pantazis DA. Comprehensive Evaluation of Models for Ammonia Binding to the Oxygen Evolving Complex of Photosystem II. J Phys Chem B 2024; 128:1333-1349. [PMID: 38299511 PMCID: PMC10875651 DOI: 10.1021/acs.jpcb.3c06304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/08/2024] [Accepted: 01/17/2024] [Indexed: 02/02/2024]
Abstract
The identity and insertion pathway of the substrate oxygen atoms that are coupled to dioxygen by the oxygen-evolving complex (OEC) remains a central question toward understanding Nature's water oxidation mechanism. In several studies, ammonia has been used as a small "water analogue" to elucidate the pathway of substrate access to the OEC and to aid in determining which of the oxygen ligands of the tetramanganese cluster are substrates for O-O bond formation. On the basis of structural and spectroscopic investigations, five first-sphere binding modes of ammonia have been suggested, involving either substitution of an existing H2O/OH-/O2- group or addition as an extra ligand to a metal ion of the Mn4CaO5 cluster. Some of these modes, specifically the ones involving substitution, have already been subject to spectroscopy-oriented quantum chemical investigations, whereas more recent suggestions that postulate the addition of ammonia have not been examined so far with quantum chemistry for their agreement with spectroscopic data. Herein, we use a common structural framework and theoretical methodology to evaluate structural models of the OEC that represent all proposed modes of first-sphere ammonia interaction with the OEC in its S2 state. Criteria include energetic, magnetic, kinetic, and spectroscopic properties compared against available experimental EPR, ENDOR, ESEEM, and EDNMR data. Our results show that models featuring ammonia replacing one of the two terminal water ligands on Mn4 align best with experimental data, while they definitively exclude substitution of a bridging μ-oxo ligand as well as incorporation of ammonia as a sixth ligand on Mn1 or Mn4.
Collapse
Affiliation(s)
- Maria Drosou
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
- Inorganic
Chemistry Laboratory, National and Kapodistrian
University of Athens, Panepistimiopolis, Zografou 15771, Greece
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
| |
Collapse
|
2
|
Ziółkowska A, Witwicki M. Understanding the Exchange Interaction between Paramagnetic Metal Ions and Radical Ligands: DFT and Ab Initio Study on Semiquinonato Cu(II) Complexes. Int J Mol Sci 2023; 24:ijms24044001. [PMID: 36835412 PMCID: PMC9959031 DOI: 10.3390/ijms24044001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023] Open
Abstract
The exchange coupling, represented by the J parameter, is of tremendous importance in understanding the reactivity and magnetic behavior of open-shell molecular systems. In the past, it was the subject of theoretical investigations, but these studies are mostly limited to the interaction between metallic centers. The exchange coupling between paramagnetic metal ions and radical ligands has hitherto received scant attention in theoretical studies, and thus the understanding of the factors governing this interaction is lacking. In this paper, we use DFT, CASSCF, CASSCF/NEVPT2, and DDCI3 methods to provide insight into exchange interaction in semiquinonato copper(II) complexes. Our primary objective is to identify structural features that affect this magnetic interaction. We demonstrate that the magnetic character of Cu(II)-semiquinone complexes are mainly determined by the relative position of the semiquinone ligand to the Cu(II) ion. The results can support the experimental interpretation of magnetic data for similar systems and can be used for the in-silico design of magnetic complexes with radical ligands.
Collapse
Affiliation(s)
- Aleksandra Ziółkowska
- Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
| | - Maciej Witwicki
- Faculty of Chemistry, Wroclaw University, F. Joliot-Curie 14, 50-283 Wroclaw, Poland
- Correspondence:
| |
Collapse
|
3
|
Tzani S, Pissas M, Psycharis V, Pantazis DA, Sanakis Y, Raptopoulou CP. Synthesis and structural, magnetic and spectroscopic characterization of iron(III) complexes with in situ formed ligands from methyl-2-pyridyl ketone transformations. Dalton Trans 2023; 52:1582-1594. [PMID: 36651584 DOI: 10.1039/d2dt03944c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Reactions of methyl-2-pyridyl ketone, pyCOMe, with FeCl3·6H2O in various solvents gave complexes [Fe4Cl6(OMe)2(L1)2]·0.7MeCN·0.4MeOH (1·0.7MeCN·0.4MeOH) and [Fe3Cl4(bicine)(L2)]·Me2CO·0.2H2O (2·Me2CO·0.2H2O). The ligands (L1)2- = pyCO(Me)CHCOpy (in 1) and (L2)2- = pyCO(Me)CH2CO(OMe)py (in 2) are formed in situ, through an aldol reaction-type mechanism between the carbanion pyC(O)CH2- (formed by the nucleophilic attack of the MeO- in pyCOMe) and pyCOMe which results in the formation of a new C-C bond. The intermediate compound undergoes attack in the -CH2- or -CO- group by a MeO- group, and the new ligands (L1)2- and (L2)2-, respectively, are formed. The molecular structure of 1 consists of three corner-sharing [Fe2O2] rhombic units in cis-arrangement. The two terminal FeIII ions display distorted square pyramidal geometry and the two central FeIII ions are distorted octahedral. The molecular structure of 2 consists of two corner-sharing [Fe2O2] rhombic units, with the two terminal FeIII ions in distorted square pyramidal geometry and the central FeIII in distorted octahedral. The differentiation in the coordination environment of the FeIII ions in 1-2 is reflected in the values of the Mössbauer hyperfine parameters. In agreement with theoretical calculations, the square pyramidal sites exhibit a smaller isomer shift value in comparison to the octahedral sites. Magnetic studies indicate antiferromagnetic interactions leading to an S = 0 ground state in 1 and to an S = 5/2 ground state in 2, consistent with Electron Paramagnetic Resonance spectroscopy. Mössbauer spectra of 2 indicate the onset of relaxation effects below 80 K. At 1.5 K the spectrum of 2 consists of magnetic sextets. The determined hyperfine magnetic fields are consistent with the exchange coupling scheme imposed by the crystal structure of 2. Theoretical calculations shed light on the differences in the electronic structure between the square pyramidal and the octahedral sites.
Collapse
Affiliation(s)
- Sofia Tzani
- Institute of Nanoscience and Nanotechnology, NCSR "Demokritos", 15310 Aghia Paraskevi, Athens, Greece.
| | - Michael Pissas
- Institute of Nanoscience and Nanotechnology, NCSR "Demokritos", 15310 Aghia Paraskevi, Athens, Greece.
| | - Vassilis Psycharis
- Institute of Nanoscience and Nanotechnology, NCSR "Demokritos", 15310 Aghia Paraskevi, Athens, Greece.
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Yiannis Sanakis
- Institute of Nanoscience and Nanotechnology, NCSR "Demokritos", 15310 Aghia Paraskevi, Athens, Greece.
| | - Catherine P Raptopoulou
- Institute of Nanoscience and Nanotechnology, NCSR "Demokritos", 15310 Aghia Paraskevi, Athens, Greece.
| |
Collapse
|
4
|
Takeyama T, Suzuki T, Kikuchi M, Kobayashi M, Oshita H, Kawashima K, Mori S, Abe H, Hoshino N, Iwatsuki S, Shimazaki Y. Solid State Characterization of One‐ and Two‐Electron Oxidized Cu
II
‐salen Complexes with
para
‐Substituents: Geometric Structure‐Magnetic Property Relationship. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Tomoyuki Takeyama
- Department of Chemistry Konan University Higashinada-ku Kobe 658-8501 Japan
| | - Takashi Suzuki
- Graduate School of Science and Engineering Ibaraki University Bunkyo Mito 310-8512 Japan
| | - Misa Kikuchi
- College of Science Ibaraki University Bunkyo Mito 310-8512 Japan
| | - Misato Kobayashi
- Department of Chemistry Konan University Higashinada-ku Kobe 658-8501 Japan
| | - Hiromi Oshita
- Institute of Materials Structure Science (IMSS) High Energy Accelerator Research Organization (KEK) 1-1 Oho, Tsukuba Ibaraki 305-0801 Japan
| | - Kyohei Kawashima
- Institute for Materials Chemistry Engineering, Kyushu University 6-1 kasuga-koen Kasuga, Fukuoka 816-8580 Japan
| | - Seiji Mori
- Graduate School of Science and Engineering Ibaraki University Bunkyo Mito 310-8512 Japan
- College of Science Ibaraki University Bunkyo Mito 310-8512 Japan
| | - Hitoshi Abe
- Graduate School of Science and Engineering Ibaraki University Bunkyo Mito 310-8512 Japan
- Institute of Materials Structure Science (IMSS) High Energy Accelerator Research Organization (KEK) 1-1 Oho, Tsukuba Ibaraki 305-0801 Japan
- School of High Energy Accelerator Science SOKENDAI (the Graduate University for Advanced Studies) 1-1 Oho, Tsukuba Ibaraki 305-0801 Japan
| | - Norihisa Hoshino
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM) Tohoku University 2-1-1 Katahira, Aoba-ku Sendai 980-8577 Japan
| | - Satoshi Iwatsuki
- Department of Chemistry Konan University Higashinada-ku Kobe 658-8501 Japan
| | - Yuichi Shimazaki
- Graduate School of Science and Engineering Ibaraki University Bunkyo Mito 310-8512 Japan
- College of Science Ibaraki University Bunkyo Mito 310-8512 Japan
| |
Collapse
|
5
|
Drosou M, Pantazis DA. Redox Isomerism in the S 3 State of the Oxygen-Evolving Complex Resolved by Coupled Cluster Theory. Chemistry 2021; 27:12815-12825. [PMID: 34288176 PMCID: PMC8518824 DOI: 10.1002/chem.202101567] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Indexed: 01/19/2023]
Abstract
The electronic and geometric structures of the water-oxidizing complex of photosystem II in the steps of the catalytic cycle that precede dioxygen evolution remain hotly debated. Recent structural and spectroscopic investigations support contradictory redox formulations for the active-site Mn4 CaOx cofactor in the final metastable S3 state. These range from the widely accepted MnIV 4 oxo-hydroxo model, which presumes that O-O bond formation occurs in the ultimate transient intermediate (S4 ) of the catalytic cycle, to a MnIII 2 MnIV 2 peroxo model representative of the contrasting "early-onset" O-O bond formation hypothesis. Density functional theory energetics of suggested S3 redox isomers are inconclusive because of extreme functional dependence. Here, we use the power of the domain-based local pair natural orbital approach to coupled cluster theory, DLPNO-CCSD(T), to present the first correlated wave function theory calculations of relative stabilities for distinct redox-isomeric forms of the S3 state. Our results enabled us to evaluate conflicting models for the S3 state of the oxygen-evolving complex (OEC) and to quantify the accuracy of lower-level theoretical approaches. Our assessment of the relevance of distinct redox-isomeric forms for the mechanism of biological water oxidation strongly disfavors the scenario of early-onset O-O formation advanced by literal interpretations of certain crystallographic models. This work serves as a case study in the application of modern coupled cluster implementations to redox isomerism problems in oligonuclear transition metal systems.
Collapse
Affiliation(s)
- Maria Drosou
- Inorganic Chemistry LaboratoryNational and Kapodistrian University of AthensPanepistimiopolisZografou15771Greece
| | - Dimitrios A. Pantazis
- Max-Planck-Institut für KohlenforschungKaiser-Wilhelm-Platz 145470Mülheim an derRuhrGermany
| |
Collapse
|
6
|
Lee HB, Shiau AA, Marchiori DA, Oyala PH, Yoo B, Kaiser JT, Rees DC, Britt RD, Agapie T. CaMn
3
IV
O
4
Cubane Models of the Oxygen‐Evolving Complex: Spin Ground States
S
<9/2 and the Effect of Oxo Protonation. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Heui Beom Lee
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| | - Angela A. Shiau
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| | - David A. Marchiori
- Department of Chemistry University of California, Davis One Shields Ave Davis CA 95616 USA
| | - Paul H. Oyala
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| | - Byung‐Kuk Yoo
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| | - Jens T. Kaiser
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| | - Douglas C. Rees
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| | - R. David Britt
- Department of Chemistry University of California, Davis One Shields Ave Davis CA 95616 USA
| | - Theodor Agapie
- Department of Chemistry and Chemical Engineering California Institute of Technology 1200 E California Blvd MC 127-72 Pasadena CA 91125 USA
| |
Collapse
|
7
|
Lee HB, Shiau AA, Marchiori DA, Oyala PH, Yoo BK, Kaiser JT, Rees DC, Britt RD, Agapie T. CaMn 3 IV O 4 Cubane Models of the Oxygen-Evolving Complex: Spin Ground States S<9/2 and the Effect of Oxo Protonation. Angew Chem Int Ed Engl 2021; 60:17671-17679. [PMID: 34042234 DOI: 10.1002/anie.202105303] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Indexed: 11/07/2022]
Abstract
We report the single crystal XRD and MicroED structure, magnetic susceptibility, and EPR data of a series of CaMn3 IV O4 and YMn3 IV O4 complexes as structural and spectroscopic models of the cuboidal subunit of the oxygen-evolving complex (OEC). The effect of changes in heterometal identity, cluster geometry, and bridging oxo protonation on the spin-state structure was investigated. In contrast to previous computational models, we show that the spin ground state of CaMn3 IV O4 complexes and variants with protonated oxo moieties need not be S=9/2. Desymmetrization of the pseudo-C3 -symmetric Ca(Y)Mn3 IV O4 core leads to a lower S=5/2 spin ground state. The magnitude of the magnetic exchange coupling is attenuated upon oxo protonation, and an S=3/2 spin ground state is observed in CaMn3 IV O3 (OH). Our studies complement the observation that the interconversion between the low-spin and high-spin forms of the S2 state is pH-dependent, suggesting that the (de)protonation of bridging or terminal oxygen atoms in the OEC may be connected to spin-state changes.
Collapse
Affiliation(s)
- Heui Beom Lee
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| | - Angela A Shiau
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| | - David A Marchiori
- Department of Chemistry, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA
| | - Paul H Oyala
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| | - Byung-Kuk Yoo
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| | - Jens T Kaiser
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| | - Douglas C Rees
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| | - R David Britt
- Department of Chemistry, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA
| | - Theodor Agapie
- Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd MC 127-72, Pasadena, CA, 91125, USA
| |
Collapse
|
8
|
Orio M, Pantazis DA. Successes, challenges, and opportunities for quantum chemistry in understanding metalloenzymes for solar fuels research. Chem Commun (Camb) 2021; 57:3952-3974. [DOI: 10.1039/d1cc00705j] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Overview of the rich and diverse contributions of quantum chemistry to understanding the structure and function of the biological archetypes for solar fuel research, photosystem II and hydrogenases.
Collapse
Affiliation(s)
- Maylis Orio
- Aix-Marseille Université
- CNRS
- iSm2
- Marseille
- France
| | - Dimitrios A. Pantazis
- Max-Planck-Institut für Kohlenforschung
- Kaiser-Wilhelm-Platz 1
- 45470 Mülheim an der Ruhr
- Germany
| |
Collapse
|
9
|
Evaluation of new low-valent computational models for the oxygen-evolving complex of photosystem II. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2020.137629] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
10
|
Tandon S, Venkatesan M, Schmitt W, Watson GW. Altering the nature of coupling by changing the oxidation state in a {Mn 6} cage. Dalton Trans 2020; 49:8086-8095. [PMID: 32458901 DOI: 10.1039/d0dt01404d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polynuclear transition metal complexes have continuously attracted interest owing to their peculiar electronic and magnetic properties which are influenced by the symmetry and connectivity of the metal centres. Understanding the full electronic picture in such cases often becomes difficult owing to the presence of multiple bridges between metal centres. We have investigated the electronic structure of a {Mn6} cage complex using computational and experimental approaches with the aim to understand the coupling between the manganese centres. The nature of the various coupling pathways has been determined using a novel methodology that involves perturbing the system while retaining the symmetry and analysing the effect on the coupling strength due to the perturbation. Furthermore, we have investigated the magnetic properties of this complex in higher oxidation states which reveals a switch in the nature of coupling from antiferromagnetic to ferromagnetic in addition to stabilisation of intermediate spin states.
Collapse
Affiliation(s)
- Swetanshu Tandon
- School of Chemistry & CRANN Institute, University of Dublin, Trinity College, Dublin 2, Ireland.
| | | | | | | |
Collapse
|
11
|
Krewald V, Neese F, Pantazis DA. Implications of structural heterogeneity for the electronic structure of the final oxygen-evolving intermediate in photosystem II. J Inorg Biochem 2019; 199:110797. [PMID: 31404888 DOI: 10.1016/j.jinorgbio.2019.110797] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/18/2019] [Accepted: 08/01/2019] [Indexed: 10/26/2022]
Abstract
Heterogeneity in intermediate catalytic states of the oxygen-evolving complex (OEC) of Photosystem II is known from a wide range of experimental and theoretical data, but its potential implications for the mechanism of water oxidation remain unexplored. We delineate the consequences of structural heterogeneity for the final step of the catalytic cycle by tracing the evolution of three spectroscopically relevant and structurally distinct components of the last metastable S3 state to the transient O2-evolving S4 state of the OEC. Using quantum chemical calculations, we show that each S3 isomer leads to a different electronic structure formulation for the active S4 state. Crucially, in addition to previously hypothesized Mn(IV)-oxyl species, we establish for the first time, how a genuine Mn(V)-oxo can be obtained in the catalytically active S4 state: this takes the form of a five-coordinate and locally high-spin (SMn = 1) Mn(V) site. This formulation for the S4 state evolves naturally from a preceding S3-state structural intermediate that contains a quasi-trigonal-bipyramidal Mn(IV) ion. The results strongly suggest that water binding in the S3 state is not prerequisite for reaching the oxygen-evolving S4 state of the complex, supporting the notion that both substrates are preloaded at the beginning of the catalytic cycle. This scenario allows true four-electron metal-centered hole accumulation to precede OO bond formation and hence the latter can proceed via a genuine even-electron mechanism. This can occur as intramolecular nucleophilic coupling of two oxo units synchronously with the binding of a water substrate for the next catalytic cycle.
Collapse
Affiliation(s)
- Vera Krewald
- Theoretische Chemie, Fachbereich Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 4, 64287 Darmstadt, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
| |
Collapse
|
12
|
Assessment of Double-Hybrid Density Functional Theory for Magnetic Exchange Coupling in Manganese Complexes. INORGANICS 2019. [DOI: 10.3390/inorganics7050057] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Molecular systems containing magnetically interacting (exchange-coupled) manganese ions are important in catalysis, biomimetic chemistry, and molecular magnetism. The reliable prediction of exchange coupling constants with quantum chemical methods is key for tracing the relationships between structure and magnetic properties in these systems. Density functional theory (DFT) in the broken-symmetry approach has been employed extensively for this purpose and hybrid functionals with moderate levels of Hartree–Fock exchange admixture have often been shown to perform adequately. Double-hybrid density functionals that introduce a second-order perturbational contribution to the Kohn–Sham energy are generally regarded as a superior approach for most molecular properties, but their performance remains unexplored for exchange-coupled manganese systems. An assessment of various double-hybrid functionals for the prediction of exchange coupling constants is presented here using a set of experimentally characterized dinuclear manganese complexes that cover a wide range of exchange coupling situations. Double-hybrid functionals perform more uniformly compared to conventional DFT methods, but they fail to deliver improved accuracy or reliability in the prediction of exchange coupling constants. Reparametrized double-hybrid density functionals (DHDFs) perform no better, and most often worse, than the original B2-PLYP double-hybrid method. All DHDFs are surpassed by the hybrid-meta-generalized gradient approximation (GGA) TPSSh functional. Possible directions for future methodological developments are discussed.
Collapse
|
13
|
Pantazis DA. Meeting the Challenge of Magnetic Coupling in a Triply-Bridged Chromium Dimer: Complementary Broken-Symmetry Density Functional Theory and Multireference Density Matrix Renormalization Group Perspectives. J Chem Theory Comput 2019; 15:938-948. [PMID: 30645093 PMCID: PMC6728064 DOI: 10.1021/acs.jctc.8b00969] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
![]()
Face-sharing
octahedral dinuclear Cr(III) compounds with d3–d3 electronic configurations represent nontrivial examples of
electronic complexity, posing particular challenges for theoretical
and computational studies. A tris-hydroxy-bridged Cr(III)–Cr(III)
system has proven to be a richly rewarding target for studies of magnetism
and electron paramagnetic resonance spectroscopy. It was also reported
to be a peculiarly difficult system to treat with density functional
theory (DFT). In this work the magnetic coupling problem for this
dimer is approached with broken-symmetry (BS)-DFT and multireference
calculations that utilize the density matrix renormalization group
(DMRG) to handle full-valence active spaces. BS-DFT is shown to recover
the correct ordering and energy spacing of Heisenberg spin states
if used in conjunction with appropriate spin projection procedures,
albeit with pronounced functional sensitivity. The contrasting conclusions
of previous studies are traced to incorrect inclusion of electronically
excited configurations. Analysis of the direct and differential overlap
of corresponding orbital pairs from the BS-DFT solution indicates
that metal–metal through-space interaction is the dominant
contributor to antiferromagnetic coupling. At the DFT level a procedure
that utilizes pseudopotential substitution is demonstrated that allows
evaluation of the direct exchange vs superexchange contributions.
A complementary description is obtained with DMRG-SCF calculations
that enable state-averaged CASSCF calculations with both metal and
bridge orbitals in the active space. A localized orbital subspace
analysis supports the DFT conclusions that in contrast to doubly bridged
isoelectronic analogues, antiferromagnetic coupling in the chromium
dimer arises primarily from direct metal–metal interaction
but is significantly enhanced by ligand-mediated superexchange.
Collapse
Affiliation(s)
- Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| |
Collapse
|
14
|
Kochem A, Faure B, Bertaina S, Rivière E, Giorgi M, Réglier M, Orio M, Simaan AJ. Magneto‐Structural and Computational Study of a Tetranuclear Copper Complex Displaying Carbonyl–π Interactions. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201801032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Amélie Kochem
- Centrale Marseille, iSm2 Aix Marseille Univ, CNRS Marseille France
| | - Bruno Faure
- Centrale Marseille, iSm2 Aix Marseille Univ, CNRS Marseille France
| | | | - Eric Rivière
- Institut de Chimie Moléculaire et des Matériaux d′Orsay, Univ Paris Sud Université Paris‐Saclay, CNRS Orsay France
| | - Michel Giorgi
- Spectropole FR1739 Aix Marseille Univ, CNRS Marseille France
| | - Marius Réglier
- Centrale Marseille, iSm2 Aix Marseille Univ, CNRS Marseille France
| | - Maylis Orio
- Centrale Marseille, iSm2 Aix Marseille Univ, CNRS Marseille France
| | - A. Jalila Simaan
- Centrale Marseille, iSm2 Aix Marseille Univ, CNRS Marseille France
| |
Collapse
|
15
|
Van Kuiken BE, Hahn AW, Nayyar B, Schiewer CE, Lee SC, Meyer F, Weyhermüller T, Nicolaou A, Cui YT, Miyawaki J, Harada Y, DeBeer S. Electronic Spectra of Iron–Sulfur Complexes Measured by 2p3d RIXS Spectroscopy. Inorg Chem 2018; 57:7355-7361. [DOI: 10.1021/acs.inorgchem.8b01010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Benjamin E. Van Kuiken
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Anselm W. Hahn
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Brahamjot Nayyar
- Department of Chemistry, University of Waterloo, Waterloo N2L 3G1, Canada
| | - Christine E. Schiewer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Sonny C. Lee
- Department of Chemistry, University of Waterloo, Waterloo N2L 3G1, Canada
| | - Franc Meyer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | | | - Yi-Tao Cui
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Jun Miyawaki
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yoshihisa Harada
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| |
Collapse
|
16
|
Buvaylo EA, Kokozay VN, Makhankova VG, Melnyk AK, Korabik M, Witwicki M, Skelton BW, Vassilyeva OY. Synthesis, Characterization, and Magnetic Properties of a Series of Copper(II) Chloride Complexes of Pyridyliminebenzoic Acids. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201701391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Elena A. Buvaylo
- Department of Chemistry Taras Shevchenko National University of Kyiv 64/13 Volodymyrska str. 01601 Kyiv Ukraine
| | - Vladimir N. Kokozay
- Department of Chemistry Taras Shevchenko National University of Kyiv 64/13 Volodymyrska str. 01601 Kyiv Ukraine
| | - Valeriya G. Makhankova
- Department of Chemistry Taras Shevchenko National University of Kyiv 64/13 Volodymyrska str. 01601 Kyiv Ukraine
| | - Andrii K. Melnyk
- Institute for Sorption and Problems of Endoecology The National Academy of Sciences of Ukraine 13 Generala Naumova str. 03164 Kyiv Ukraine
| | - Maria Korabik
- Faculty of Chemistry University of Wroclaw F. Joliot‐Curie 14 50‐383 Wroclaw Poland
| | - Maciej Witwicki
- Faculty of Chemistry University of Wroclaw F. Joliot‐Curie 14 50‐383 Wroclaw Poland
| | - Brian W. Skelton
- School of Molecular Sciences, M310 University of Western Australia 6009 Perth WA Australia
| | - Olga Yu. Vassilyeva
- Department of Chemistry Taras Shevchenko National University of Kyiv 64/13 Volodymyrska str. 01601 Kyiv Ukraine
| |
Collapse
|
17
|
Beal NJ, Corry TA, O'Malley PJ. A Comparison of Experimental and Broken Symmetry Density Functional Theory (BS-DFT) Calculated Electron Paramagnetic Resonance (EPR) Parameters for Intermediates Involved in the S 2 to S 3 State Transition of Nature's Oxygen Evolving Complex. J Phys Chem B 2018; 122:1394-1407. [PMID: 29300480 DOI: 10.1021/acs.jpcb.7b10843] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A broken symmetry density functional theory (BS-DFT) magnetic analysis of the S2, S2YZ•, and S3 states of Nature's oxygen evolving complex is performed for both the native Ca and Sr substituted forms. Good agreement with experiment is observed between the tyrosyl calculated g-tensor and 1H hyperfine couplings for the native Ca form. Changes in the hydrogen bonding environment of the tyrosyl radical in S2YZ• caused by Sr substitution lead to notable changes in the calculated g-tensor of the tyrosyl radical. Comparison of calculated and experimental 55Mn hyperfine couplings for the S3 state presently favors an open cubane form of the complex with an additional OH ligand coordinating to MnD. In Ca models, this additional ligation can arise by closed-cubane form deprotonation of the Ca ligand W3 in the S2YZ• state accompanied by spontaneous movement to the vacant Mn coordination site or by addition of an external OH group. For the Sr form, no spontaneous movement of W3 to the vacant Mn coordination site is observed in contrast to the native Ca form, a difference which may lead to the reduced catalytic activity of the Sr substituted form. BS-DFT studies on peroxo models of S3 as indicated by a recent X-ray free electron laser (XFEL) crystallography study give rise to a structural model compatible with experimental data and an S = 3 ground state compatible with EPR studies.
Collapse
Affiliation(s)
- Nathan J Beal
- School of Chemistry, The University of Manchester , Manchester M13 9PL, U.K
| | - Thomas A Corry
- School of Chemistry, The University of Manchester , Manchester M13 9PL, U.K
| | - Patrick J O'Malley
- School of Chemistry, The University of Manchester , Manchester M13 9PL, U.K
| |
Collapse
|
18
|
Majee MC, Towsif Abtab SM, Mondal D, Maity M, Weselski M, Witwicki M, Bieńko A, Antkowiak M, Kamieniarz G, Chaudhury M. Synthesis and magneto-structural studies on a new family of carbonato bridged 3d–4f complexes featuring a [CoII3LnIII3(CO3)] (Ln = La, Gd, Tb, Dy and Ho) core: slow magnetic relaxation displayed by the cobalt(ii)–dysprosium(iii) analogue. Dalton Trans 2018; 47:3425-3439. [DOI: 10.1039/c7dt04389a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new series of carbonato-bridged complexes containing a CoII3LnIII3 core have been synthesized.
Collapse
Affiliation(s)
- Mithun Chandra Majee
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700 032
- India
| | - Sk Md Towsif Abtab
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700 032
- India
| | - Dhrubajyoti Mondal
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700 032
- India
| | - Manoranjan Maity
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700 032
- India
| | - Marek Weselski
- Faculty of Chemistry
- University of Wroclaw
- 50-383 Wroclaw
- Poland
| | - Maciej Witwicki
- Faculty of Chemistry
- University of Wroclaw
- 50-383 Wroclaw
- Poland
| | - Alina Bieńko
- Faculty of Chemistry
- University of Wroclaw
- 50-383 Wroclaw
- Poland
| | - Michał Antkowiak
- Faculty of Physics
- A. Mickiewicz University
- PL-61-614 Poznań
- Poland
| | | | - Muktimoy Chaudhury
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700 032
- India
| |
Collapse
|
19
|
Roemelt M, Krewald V, Pantazis DA. Exchange Coupling Interactions from the Density Matrix Renormalization Group and N-Electron Valence Perturbation Theory: Application to a Biomimetic Mixed-Valence Manganese Complex. J Chem Theory Comput 2017; 14:166-179. [PMID: 29211960 DOI: 10.1021/acs.jctc.7b01035] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The accurate description of magnetic level energetics in oligonuclear exchange-coupled transition-metal complexes remains a formidable challenge for quantum chemistry. The density matrix renormalization group (DMRG) brings such systems for the first time easily within reach of multireference wave function methods by enabling the use of unprecedentedly large active spaces. But does this guarantee systematic improvement in predictive ability and, if so, under which conditions? We identify operational parameters in the use of DMRG using as a test system an experimentally characterized mixed-valence bis-μ-oxo/μ-acetato Mn(III,IV) dimer, a model for the oxygen-evolving complex of photosystem II. A complete active space of all metal 3d and bridge 2p orbitals proved to be the smallest meaningful starting point; this is readily accessible with DMRG and greatly improves on the unrealistic metal-only configuration interaction or complete active space self-consistent field (CASSCF) values. Orbital optimization is critical for stabilizing the antiferromagnetic state, while a state-averaged approach over all spin states involved is required to avoid artificial deviations from isotropic behavior that are associated with state-specific calculations. Selective inclusion of localized orbital subspaces enables probing the relative contributions of different ligands and distinct superexchange pathways. Overall, however, full-valence DMRG-CASSCF calculations fall short of providing a quantitative description of the exchange coupling owing to insufficient recovery of dynamic correlation. Quantitatively accurate results can be achieved through a DMRG implementation of second order N-electron valence perturbation theory (NEVPT2) in conjunction with a full-valence metal and ligand active space. Perspectives for future applications of DMRG-CASSCF/NEVPT2 to exchange coupling in oligonuclear clusters are discussed.
Collapse
Affiliation(s)
- Michael Roemelt
- Lehrstuhl für Theoretische Chemie, Ruhr-University Bochum , 44780 Bochum, Germany.,Max Planck Institute for Coal Research, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Vera Krewald
- Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom
| | - Dimitrios A Pantazis
- Max Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany
| |
Collapse
|
20
|
Tesmar A, Witwicki M, Wyrzykowski D, Sikorski A, Jacewicz D, Drzeżdżon J, Chmurzyński L. Structure and characterization of physicochemical and magnetic properties of new complex containing monobridged oxygen copper(II) dinuclear cation. Polyhedron 2017. [DOI: 10.1016/j.poly.2017.02.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
21
|
Family of MnIII4LnIII2 (LnIII= SmIII, GdIII, DyIII) coordination clusters: Experimental and theoretical investigations. Polyhedron 2016. [DOI: 10.1016/j.poly.2016.08.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
22
|
Dresselhaus T, Eusterwiemann S, Matuschek DR, Daniliuc CG, Janka O, Pöttgen R, Studer A, Neugebauer J. Black-box determination of temperature-dependent susceptibilities for crystalline organic radicals with complex magnetic topologies. Phys Chem Chem Phys 2016; 18:28262-28273. [PMID: 27711591 DOI: 10.1039/c6cp05875b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In all but the simplest crystal structures, the identification of all relevant interactions between magnetic sites as well as the setup of magnetic model spaces, which are necessary for modeling macroscopic magnetism, are tedious and error-prone tasks. Here, we present a procedure to generate magnetic susceptibility versus temperature curves using only a crystal structure as input. The procedure, which is based on the first-principles bottom-up approach [Deumal et al., J. Phys. Chem. A, 2002, 106, 1299], is designed in a way to require as little user interference as possible. We employ quantum chemical calculations to parametrize a Heisenberg Hamiltonian, which is set up and diagonalized for different magnetic model spaces to ensure convergence of the model. We apply the procedure to several 6-oxo-verdazyl radical structures, including newly synthesized compounds, and compare the results to data we obtained from magnetic susceptibility measurements as well as published data to further benchmark our procedure. Furthermore, the different impact of certain dominating coupling constants is systematically analyzed.
Collapse
Affiliation(s)
- Thomas Dresselhaus
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany. and Center for Multiscale Theory and Computation, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Steffen Eusterwiemann
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - David R Matuschek
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - Oliver Janka
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, 48149 Münster, Germany
| | - Rainer Pöttgen
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - Johannes Neugebauer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany. and Center for Multiscale Theory and Computation, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| |
Collapse
|
23
|
Krewald V, Retegan M, Neese F, Lubitz W, Pantazis DA, Cox N. Spin State as a Marker for the Structural Evolution of Nature’s Water-Splitting Catalyst. Inorg Chem 2015; 55:488-501. [DOI: 10.1021/acs.inorgchem.5b02578] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Vera Krewald
- Max Planck Institute for Chemical Energy Conversion, Stiftstr.
34–36, Mülheim an der Ruhr 45470, Germany
| | - Marius Retegan
- Max Planck Institute for Chemical Energy Conversion, Stiftstr.
34–36, Mülheim an der Ruhr 45470, Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion, Stiftstr.
34–36, Mülheim an der Ruhr 45470, Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion, Stiftstr.
34–36, Mülheim an der Ruhr 45470, Germany
| | - Dimitrios A. Pantazis
- Max Planck Institute for Chemical Energy Conversion, Stiftstr.
34–36, Mülheim an der Ruhr 45470, Germany
| | - Nicholas Cox
- Max Planck Institute for Chemical Energy Conversion, Stiftstr.
34–36, Mülheim an der Ruhr 45470, Germany
| |
Collapse
|
24
|
Krewald V, Neese F, Pantazis DA. Resolving the Manganese Oxidation States in the Oxygen-evolving Catalyst of Natural Photosynthesis. Isr J Chem 2015. [DOI: 10.1002/ijch.201500051] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
25
|
Krewald V, Retegan M, Cox N, Messinger J, Lubitz W, DeBeer S, Neese F, Pantazis DA. Metal oxidation states in biological water splitting. Chem Sci 2015; 6:1676-1695. [PMID: 29308133 PMCID: PMC5639794 DOI: 10.1039/c4sc03720k] [Citation(s) in RCA: 230] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 12/31/2014] [Indexed: 12/20/2022] Open
Abstract
A central question in biological water splitting concerns the oxidation states of the manganese ions that comprise the oxygen-evolving complex of photosystem II.
A central question in biological water splitting concerns the oxidation states of the manganese ions that comprise the oxygen-evolving complex of photosystem II. Understanding the nature and order of oxidation events that occur during the catalytic cycle of five Si states (i = 0–4) is of fundamental importance both for the natural system and for artificial water oxidation catalysts. Despite the widespread adoption of the so-called “high-valent scheme”—where, for example, the Mn oxidation states in the S2 state are assigned as III, IV, IV, IV—the competing “low-valent scheme” that differs by a total of two metal unpaired electrons (i.e. III, III, III, IV in the S2 state) is favored by several recent studies for the biological catalyst. The question of the correct oxidation state assignment is addressed here by a detailed computational comparison of the two schemes using a common structural platform and theoretical approach. Models based on crystallographic constraints were constructed for all conceivable oxidation state assignments in the four (semi)stable S states of the oxygen evolving complex, sampling various protonation levels and patterns to ensure comprehensive coverage. The models are evaluated with respect to their geometric, energetic, electronic, and spectroscopic properties against available experimental EXAFS, XFEL-XRD, EPR, ENDOR and Mn K pre-edge XANES data. New 2.5 K 55Mn ENDOR data of the S2 state are also reported. Our results conclusively show that the entire S state phenomenology can only be accommodated within the high-valent scheme by adopting a single motif and protonation pattern that progresses smoothly from S0 (III, III, III, IV) to S3 (IV, IV, IV, IV), satisfying all experimental constraints and reproducing all observables. By contrast, it was impossible to construct a consistent cycle based on the low-valent scheme for all S states. Instead, the low-valent models developed here may provide new insight into the over-reduced S states and the states involved in the assembly of the catalytically active water oxidizing cluster.
Collapse
Affiliation(s)
- Vera Krewald
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| | - Marius Retegan
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| | - Nicholas Cox
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| | - Johannes Messinger
- Department of Chemistry , Chemical Biological Center (KBC) , Umeå University , 90187 Umeå , Sweden
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| | - Dimitrios A Pantazis
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38 , 45470 Mülheim an der Ruhr , Germany .
| |
Collapse
|
26
|
Retegan M, Cox N, Pantazis DA, Neese F. A first-principles approach to the calculation of the on-site zero-field splitting in polynuclear transition metal complexes. Inorg Chem 2014; 53:11785-93. [PMID: 25340874 DOI: 10.1021/ic502081c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The interpretation of electron paramagnetic resonance spectra of polynuclear transition metal complexes in terms of individual contributions from each paramagnetic center can be greatly facilitated by the availability of theoretical methods that enable the reliable prediction of local spectroscopic parameters. In this work we report an approach that enables the application of multireference ab initio methods for the calculation of local zero field splitting tensors, one of the leading terms in the spin Hamiltonian for exchange-coupled systems of high nuclearity. The method referred to as local complete active space configuration interaction (L-CASCI) represents a multireference calculation with an active space composed of local orbitals of the center of interest. By successive permutation of the active space to include the localized orbitals corresponding to a particular center of the complex, all on-site parameters can be easily obtained at a high-level of theory with a corresponding low computational cost. Benchmark calculations on synthetic complexes confirm the validity of the approach. As an example of the applicability of the L-CASCI method to large systems, we determine the local anisotropy of the Mn(III) ion of the tetranuclear manganese cluster of photosystem II in both structural forms of its S2 state.
Collapse
Affiliation(s)
- Marius Retegan
- Max Planck Institute for Chemical Energy Conversion , Stiftstr. 34-38, 45470 Mülheim an der Ruhr, Germany
| | | | | | | |
Collapse
|
27
|
Ledesma GN, Anxolabéhère-Mallart E, Rivière E, Mallet-Ladeira S, Hureau C, Signorella SR. Trinuclear Manganese Complexes of Unsymmetrical Polypodal Diamino N3O3 Ligands with an Unusual [Mn3(μ-OR)4]5+ Triangular Core: Synthesis, Characterization, and Catalase Activity. Inorg Chem 2014; 53:2545-53. [DOI: 10.1021/ic402843y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gabriela N. Ledesma
- IQUIR (Instituto de Química Rosario),
Consejo Nacional de Investigaciones Científicas y Técnicas
(CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina
| | - Elodie Anxolabéhère-Mallart
- Laboratoire Electrochimie
Moléculaire-UMR CNRS 7591, University of Paris Diderot, Sorbonne
Paris Cité15 rue Jean de Baïf, 75251 Paris, Cedex 13, France
| | - Eric Rivière
- ICMMO-UMR 8182, Equipe Chimie Inorganique, Université Paris-Sud, 91405 Orsay, France
| | - Sonia Mallet-Ladeira
- Institut de Chimie de Toulouse, FR 2599, 118 Route de Narbonne, F-31062 Toulouse, France
| | - Christelle Hureau
- CNRS, LCC (Laboratoire
de Chimie de Coordination) and UPS, INPT,
LCC, Université de Toulouse, 205 route de Narbonne, F-31077 Toulouse, France
| | - Sandra R. Signorella
- IQUIR (Instituto de Química Rosario),
Consejo Nacional de Investigaciones Científicas y Técnicas
(CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina
| |
Collapse
|
28
|
Krewald V, Lassalle-Kaiser B, Boron TT, Pollock CJ, Kern J, Beckwith MA, Yachandra VK, Pecoraro VL, Yano J, Neese F, DeBeer S. The protonation states of oxo-bridged Mn(IV) dimers resolved by experimental and computational Mn K pre-edge X-ray absorption spectroscopy. Inorg Chem 2013; 52:12904-14. [PMID: 24161030 PMCID: PMC3911776 DOI: 10.1021/ic4008203] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In nature, the protonation of oxo bridges is a commonly encountered mechanism for fine-tuning chemical properties and reaction pathways. Often, however, the protonation states are difficult to establish experimentally. This is of particular importance in the oxygen evolving complex of photosystem II, where identification of the bridging oxo protonation states is one of the essential requirements toward unraveling the mechanism. In order to establish a combined experimental and theoretical protocol for the determination of protonation states, we have systematically investigated a series of Mn model complexes by Mn K pre-edge X-ray absorption spectroscopy. An ideal test case for selective bis-μ-oxo-bridge protonation in a Mn dimer is represented by the system [Mn(IV)2(salpn)2(μ-OHn)2](n+). Although the three species [Mn(IV)2(salpn)2(μ-O)2], [Mn(IV)2(salpn)2(μ-O)(μ-OH)](+) and [Mn(IV)2(salpn)2(μ-OH)2](2+) differ only in the protonation of the oxo bridges, they exhibit distinct differences in the pre-edge region while maintaining the same edge energy. The experimental spectra are correlated in detail to theoretically calculated spectra. A time-dependent density functional theory approach for calculating the pre-edge spectra of molecules with multiple metal centers is presented, using both high spin (HS) and broken symmetry (BS) electronic structure solutions. The most intense pre-edge transitions correspond to an excitation of the Mn 1s core electrons into the unoccupied orbitals of local e(g) character (d(z)(2) and d(xy) based in the chosen coordinate system). The lowest energy experimental feature is dominated by excitations of 1s-α electrons, and the second observed feature is primarily attributed to 1s-β electron excitations. The observed energetic separation is due to spin polarization effects in spin-unrestricted density functional theory and models final state multiplet effects. The effects of spin polarization on the calculated Mn K pre-edge spectra, in both the HS and BS solutions, are discussed in terms of the strength of the antiferromagnetic coupling and associated changes in the covalency of Mn-O bonds. The information presented in this paper is complemented with the X-ray emission spectra of the same compounds published in an accompanying paper. Taken together, the two studies provide the foundation for a better understanding of the X-ray spectroscopic data of the oxygen evolving complex (OEC) in photosystem II.
Collapse
Affiliation(s)
- Vera Krewald
- Max-Planck-Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Benedikt Lassalle-Kaiser
- Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Thaddeus T. Boron
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Christopher J. Pollock
- Max-Planck-Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Jan Kern
- Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Martha A. Beckwith
- Max-Planck-Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Vittal K. Yachandra
- Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Vincent L. Pecoraro
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Junko Yano
- Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Frank Neese
- Max-Planck-Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max-Planck-Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| |
Collapse
|
29
|
Yu Y, Li C, Yin B, Li JL, Huang YH, Wen ZY, Jiang ZY. Are trinuclear superhalogens promising candidates for building blocks of novel magnetic materials? A theoretical prospect from combined broken-symmetry density functional theory and ab initio study. J Chem Phys 2013; 139:054305. [DOI: 10.1063/1.4817189] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
|
30
|
Retegan M, Neese F, Pantazis DA. Convergence of QM/MM and Cluster Models for the Spectroscopic Properties of the Oxygen-Evolving Complex in Photosystem II. J Chem Theory Comput 2013; 9:3832-42. [PMID: 26584129 DOI: 10.1021/ct400477j] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The latest crystal structure of photosystem II at 1.9 Å resolution, which resolves the topology of the Mn4CaO5 oxygen evolving complex (OEC) at atomistic detail, enables a better correlation between structural features and spectroscopic properties than ever before. Building on the refined crystallographic model of the OEC and the protein, we present combined quantum mechanical/molecular mechanical (QM/MM) studies of the spectroscopic properties of the natural catalyst embedded in the protein matrix. Focusing on the S2 state of the catalytic cycle, we examine the convergence of not only structural parameters but also of the intracluster magnetic interactions in terms of exchange coupling constants and of experimentally relevant (55)Mn, (17)O, and (14)N hyperfine coupling constants with respect to QM/MM partitioning using five QM regions of increasing size. This enables us to assess the performance of the method and to probe second sphere effects by identifying amino acid residues that principally affect the spectroscopic properties of the OEC. Comparison between QM-only and QM/MM treatments reveals that whereas QM/MM models converge quickly to stable values, the QM cluster models need to incorporate significantly larger parts of the second coordination sphere and surrounding water molecules to achieve convergence for certain properties. This is mainly due to the sensitivity of the QM-only models to fluctuations in the hydrogen bonding network and ligand acidity. Additionally, a hydrogen bond that is typically omitted in QM-only treatments is shown to determine the hyperfine coupling tensor of the unique Mn(III) ion by regulating the rotation plane of the ligated D1-His332 imidazole ring, the only N-donor ligand of the OEC.
Collapse
Affiliation(s)
- Marius Retegan
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-38, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-38, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A Pantazis
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-38, 45470 Mülheim an der Ruhr, Germany
| |
Collapse
|
31
|
Sakamoto R, Kambe T, Tsukada S, Takada K, Hoshiko K, Kitagawa Y, Okumura M, Nishihara H. π-Conjugated trinuclear group-9 metalladithiolenes with a triphenylene backbone. Inorg Chem 2013; 52:7411-6. [PMID: 23758171 DOI: 10.1021/ic400110z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Previously, we synthesized π-conjugated trinuclear metalladithiolene complexes based on benzenehexathiol (J. Chem. Soc., Dalton Trans.1998, 2651; Dalton Trans.2009, 1939; Inorg. Chem.2011, 50, 6856). Here we report trinuclear complexes with a triphenylene backbone. A reaction with triphenylenehexathiol and group 9 metal precursors in the presence of triethylamine gives rise to trinuclear complexes 9-11. The planar structure of 11 is determined using single crystal X-ray diffraction analysis. The ligand-to-metal charge transfer bands of 9-11 move to longer wavelengths compared with those of mononuclear 12-14. Electrochemical measurements disclose that the one-electron and two-electron reduced mixed-valent states are stabilized thermodynamically. UV-vis-NIR spectroscopy for the reduced species of 9 identifies intervalence charge transfer bands for 9(-) and 9(2-), substantiating the existence of electronic communication among the three metal nuclei. These observations prove that the triphenylene backbone transmits π-conjugation among the three metalladithiolene units.
Collapse
Affiliation(s)
- Ryota Sakamoto
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Tokyo 113-0033, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Phillips JJ, Peralta JE. Towards the blackbox computation of magnetic exchange coupling parameters in polynuclear transition-metal complexes: Theory, implementation, and application. J Chem Phys 2013; 138:174115. [DOI: 10.1063/1.4802776] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
33
|
Krewald V, Neese F, Pantazis DA. On the magnetic and spectroscopic properties of high-valent Mn3CaO4 cubanes as structural units of natural and artificial water-oxidizing catalysts. J Am Chem Soc 2013; 135:5726-39. [PMID: 23527603 DOI: 10.1021/ja312552f] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Mn(IV)3CaO4 cubane is a structural motif present in the oxygen-evolving complex (OEC) of photosystem II and in water-oxidizing Mn/Ca layered oxides. This work investigates the magnetic and spectroscopic properties of two recently synthesized complexes and a series of idealized models that incorporate this structural unit. Magnetic interactions, accessible spin states, and (55)Mn isotropic hyperfine couplings are computed with quantum chemical methods and form the basis for structure-property correlations. Additionally, the effects of oxo-bridge protonation and one-electron reduction are examined. The calculated properties are found to be in excellent agreement with available experimental data. It is established that all synthetic and model Mn(IV)3CaO4 cubane complexes have the same high-spin S = (9)/2 ground state. The magnetic coupling conditions under which different ground spin states can be accessed are determined. Substitution of Mn(IV) magnetic centers by diamagnetic ions [e.g., Ge(IV)] allows one to "switch off" specific spin sites in order to examine the magnetic orbitals along individual Mn-Mn exchange pathways, which confirms the predominance of ferromagnetic interactions within the cubane framework. The span of the Heisenberg spin ladder is found to correlate inversely with the number of protonated oxo bridges. Energetic comparisons for protonated models show that the tris-μ-oxo bridge connecting only Mn ions in the cubane has the lowest proton affinity and that the average relaxation energy per additional proton is on the order of 18 kcal·mol(-1), thus making access to ground states other than the high-spin S = (9)/2 state in these cubanes unlikely. The relevance of these cubanes for the OEC and synthetic oxides is discussed.
Collapse
Affiliation(s)
- Vera Krewald
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-38, 45470 Mülheim an der Ruhr, Germany
| | | | | |
Collapse
|
34
|
Harvey MA, Suarez S, Doctorovich F, Baggio R. Tris(1,10-phenanthroline-κ(2) N,N')nickel(II) hexa-oxido-μ-peroxido-disulfate-(VI) N,N-dimethyl-formamide disolvate monohydrate. Acta Crystallogr Sect E Struct Rep Online 2013; 69:m63-m64. [PMID: 23476355 PMCID: PMC3588241 DOI: 10.1107/s1600536812050775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2012] [Accepted: 12/13/2012] [Indexed: 06/01/2023]
Abstract
The asymmetric unit of the title complex, [Ni(C12H8N2)3]S2O8·2C3H7NO·H2O, consists of a complex [Ni(phen)3](2+) cation and one isolated pds anion, with two DMF mol-ecules and one water mol-ecule as solvates (where phen is 1,10-phenanthroline, pds is the hexa-oxido-μ-peroxoido-di-sulf-ate dianion and DMF is dimethyl-formamide). The [Ni(phen)3](2+) cation is regular, with an almost ideal Ni(II) bond-valence sum of 2.07 v.u. The group, as well as the water solvent mol-ecule, are well behaved in terms of crystallographic order, but the remaining three mol-ecules in the structure display different kinds of disorder, viz. the two DMF mol-ecules mimic a twofold splitting and the pds anion has both S atoms clamped at well-determined positions but with a not-too-well-defined central part. These peculiar behaviours are a consequence of the hydrogen-bonding inter-actions: the outermost SO3 parts of the pds anion are heavily connected to the complex cations via C-H⋯O hydrogen bonding, generating an [Ni(phen)3]pds network and providing for the stability of the terminal pds sites. Also, the water solvent mol-ecule is strongly bound to the structure (being a donor of two strong bonds and an acceptor of one) and is accordingly perfectly ordered. The peroxide O atoms in the pds middle region, instead, appear as much less restrained into their sites, which may explain their tendency to disorder. The cation-anion network leaves large embedded holes, amounting to about 28% of the total crystal volume, which are occupied by the DMF mol-ecules. The latter are weakly inter-acting with the rest of the structure, which renders them much more labile and, accordingly, prone to disorder.
Collapse
Affiliation(s)
- Miguel Angel Harvey
- Facultad de Ciencias Naturales, Universidad Nacional de la Patagonia S.J.B., Sede Trelew, 9100 Trelew, Chubut, Argentina
- CenPat, CONICET, 9120 Puerto Madryn, Chubut, Argentina
| | - Sebastián Suarez
- Departamento de Química Inorgánica, Analítica y Química, Física/INQUIMAE–CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Fabio Doctorovich
- Departamento de Química Inorgánica, Analítica y Química, Física/INQUIMAE–CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ricardo Baggio
- Gerencia de Investigación y Aplicaciones, Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina
| |
Collapse
|
35
|
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
| |
Collapse
|
36
|
Vaddypally S, Kondaveeti SK, Zdilla MJ. Synthesis of a High-Valent, Four-Coordinate Manganese Cubane Cluster with a Pendant Mn Atom: Photosystem II-Inspired Manganese–Nitrogen Clusters. Inorg Chem 2012; 51:3950-2. [DOI: 10.1021/ic300502s] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shivaiah Vaddypally
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
19122,
United States
| | - Sandeep K. Kondaveeti
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
19122,
United States
| | - Michael J. Zdilla
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania
19122,
United States
| |
Collapse
|
37
|
Ames W, Pantazis DA, Krewald V, Cox N, Messinger J, Lubitz W, Neese F. Theoretical evaluation of structural models of the S2 state in the oxygen evolving complex of Photosystem II: protonation states and magnetic interactions. J Am Chem Soc 2011; 133:19743-57. [PMID: 22092013 DOI: 10.1021/ja2041805] [Citation(s) in RCA: 232] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protonation states of water ligands and oxo bridges are intimately involved in tuning the electronic structures and oxidation potentials of the oxygen evolving complex (OEC) in Photosystem II, steering the mechanistic pathway, which involves at least five redox state intermediates S(n) (n = 0-4) resulting in the oxidation of water to molecular oxygen. Although protons are practically invisible in protein crystallography, their effects on the electronic structure and magnetic properties of metal active sites can be probed using spectroscopy. With the twin purpose of aiding the interpretation of the complex electron paramagnetic resonance (EPR) spectroscopic data of the OEC and of improving the view of the cluster at the atomic level, a complete set of protonation configurations for the S(2) state of the OEC were investigated, and their distinctive effects on magnetic properties of the cluster were evaluated. The most recent X-ray structure of Photosystem II at 1.9 Å resolution was used and refined to obtain the optimum structure for the Mn(4)O(5)Ca core within the protein pocket. Employing this model, a set of 26 structures was constructed that tested various protonation scenarios of the water ligands and oxo bridges. Our results suggest that one of the two water molecules that are proposed to coordinate the outer Mn ion (Mn(A)) of the cluster is deprotonated in the S(2) state, as this leads to optimal experimental agreement, reproducing the correct ground state spin multiplicity (S = 1/2), spin expectation values, and EXAFS-derived metal-metal distances. Deprotonation of Ca(2+)-bound water molecules is strongly disfavored in the S(2) state, but dissociation of one of the two water ligands appears to be facile. The computed isotropic hyperfine couplings presented here allow distinctions between models to be made and call into question the assumption that the largest coupling is always attributable to Mn(III). The present results impose limits for the total charge and the proton configuration of the OEC in the S(2) state, with implications for the cascade of events in the Kok cycle and for the water splitting mechanism.
Collapse
Affiliation(s)
- William Ames
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstr. 34-36, D-45470 Mülheim an der Ruhr, Germany
| | | | | | | | | | | | | |
Collapse
|
38
|
A new tetranuclear copper(II) complex with oximate bridges: Structure, magnetic properties and DFT study. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.07.048] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
39
|
Cox N, Ames W, Epel B, Kulik LV, Rapatskiy L, Neese F, Messinger J, Wieghardt K, Lubitz W. Electronic structure of a weakly antiferromagnetically coupled Mn(II)Mn(III) model relevant to manganese proteins: a combined EPR, 55Mn-ENDOR, and DFT study. Inorg Chem 2011; 50:8238-51. [PMID: 21834536 DOI: 10.1021/ic200767e] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
An analysis of the electronic structure of the [Mn(II)Mn(III)(μ-OH)-(μ-piv)(2)(Me(3)tacn)(2)](ClO(4))(2) (PivOH) complex is reported. It displays features that include: (i) a ground 1/2 spin state; (ii) a small exchange (J) coupling between the two Mn ions; (iii) a mono-μ-hydroxo bridge, bis-μ-carboxylato motif; and (iv) a strongly coupled, terminally bound N ligand to the Mn(III). All of these features are observed in structural models of the oxygen evolving complex (OEC). Multifrequency electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) measurements were performed on this complex, and the resultant spectra simulated using the Spin Hamiltonian formalism. The strong field dependence of the (55)Mn-ENDOR constrains the (55)Mn hyperfine tensors such that a unique solution for the electronic structure can be deduced. Large hyperfine anisotropy is required to reproduce the EPR/ENDOR spectra for both the Mn(II) and Mn(III) ions. The large effective hyperfine tensor anisotropy of the Mn(II), a d(5) ion which usually exhibits small anisotropy, is interpreted within a formalism in which the fine structure tensor of the Mn(III) ion strongly perturbs the zero-field energy levels of the Mn(II)Mn(III) complex. An estimate of the fine structure parameter (d) for the Mn(III) of -4 cm(-1) was made, by assuming the intrinsic anisotropy of the Mn(II) ion is small. The magnitude of the fine structure and intrinsic (onsite) hyperfine tensor of the Mn(III) is consistent with the known coordination environment of the Mn(III) ion as seen from its crystal structure. Broken symmetry density functional theory (DFT) calculations were performed on the crystal structure geometry. DFT values for both the isotropic and the anisotropic components of the onsite (intrinsic) hyperfine tensors match those inferred from the EPR/ENDOR simulations described above, to within 5%. This study demonstrates that DFT calculations provide reliable estimates for spectroscopic observables of mixed valence Mn complexes, even in the limit where the description of a well isolated S = 1/2 ground state begins to break down.
Collapse
Affiliation(s)
- Nicholas Cox
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Romain S, Rich J, Sens C, Stoll T, Benet-Buchholz J, Llobet A, Rodriguez M, Romero I, Clérac R, Mathonière C, Duboc C, Deronzier A, Collomb MN. Multireversible Redox Processes in Pentanuclear Bis(Triple-Helical) Manganese Complexes Featuring an Oxo-Centered triangular {MnII2MnIII(μ3-O)}5+ or {MnIIMnIII2(μ3-O)}6+ Core Wrapped by Two {MnII2(bpp)3}−. Inorg Chem 2011; 50:8427-36. [DOI: 10.1021/ic201009z] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sophie Romain
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, E-43007 Tarragona, Spain
| | - Jordi Rich
- Departament de Química, Universitat de Girona and Serveis Tecnics de Recerca, Campus de Montilivi, E-17071 Girona, Spain
| | - Cristina Sens
- Departament de Química, Universitat de Girona and Serveis Tecnics de Recerca, Campus de Montilivi, E-17071 Girona, Spain
| | - Thibaut Stoll
- Université Joseph Fourier Grenoble 1/CNRS, Département de Chimie Moléculaire, UMR-5250, Laboratoire de Chimie Inorganique Redox, Institut de Chimie Moléculaire de Grenoble FR-CNRS-2607, BP-53, 38041 Grenoble Cedex 9, France
| | - Jordi Benet-Buchholz
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, E-43007 Tarragona, Spain
| | - Antoni Llobet
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, E-43007 Tarragona, Spain
- Departament de Química, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193 Barcelona, Spain
| | - Montserrat Rodriguez
- Departament de Química, Universitat de Girona and Serveis Tecnics de Recerca, Campus de Montilivi, E-17071 Girona, Spain
| | - Isabel Romero
- Departament de Química, Universitat de Girona and Serveis Tecnics de Recerca, Campus de Montilivi, E-17071 Girona, Spain
| | - Rodolphe Clérac
- CNRS, UPR 8641, Centre de Recherche Paul Pascal (CRPP), Equipe “Matériaux Moléculaires Magnétiques”, 115 avenue du Dr. Albert Schweitzer, Pessac, F-33600, France
- Université de Bordeaux, UPR 8641, Pessac, F-33600, France
| | - Corine Mathonière
- CNRS, Université de Bordeaux, ICMCB, 87 avenue du Dr. Albert Schweitzer, Pessac, F-33600, France
| | - Carole Duboc
- Université Joseph Fourier Grenoble 1/CNRS, Département de Chimie Moléculaire, UMR-5250, Laboratoire de Chimie Inorganique Redox, Institut de Chimie Moléculaire de Grenoble FR-CNRS-2607, BP-53, 38041 Grenoble Cedex 9, France
| | - Alain Deronzier
- Université Joseph Fourier Grenoble 1/CNRS, Département de Chimie Moléculaire, UMR-5250, Laboratoire de Chimie Inorganique Redox, Institut de Chimie Moléculaire de Grenoble FR-CNRS-2607, BP-53, 38041 Grenoble Cedex 9, France
| | - Marie-Noëlle Collomb
- Université Joseph Fourier Grenoble 1/CNRS, Département de Chimie Moléculaire, UMR-5250, Laboratoire de Chimie Inorganique Redox, Institut de Chimie Moléculaire de Grenoble FR-CNRS-2607, BP-53, 38041 Grenoble Cedex 9, France
| |
Collapse
|
41
|
Giri S, Biswas S, Drew MG, Ghosh A, Saha SK. Structure and magnetic properties of a tetranuclear Cu(II) complex containing the 2-(pyridine-2-yliminomethyl)-phenol ligand. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2010.12.069] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
42
|
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.
Collapse
Affiliation(s)
- Nicholas Cox
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Neese F, Pantazis DA. What is not required to make a single molecule magnet. Faraday Discuss 2011; 148:229-38; discussion 299-314. [DOI: 10.1039/c005256f] [Citation(s) in RCA: 271] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
44
|
Compain JD, Mialane P, Dolbecq A, Mbomekallé IM, Marrot J, Sécheresse F, Duboc C, Rivière E. Structural, Magnetic, EPR, and Electrochemical Characterizations of a Spin-Frustrated Trinuclear CrIII Polyoxometalate and Study of Its Reactivity with Lanthanum Cations. Inorg Chem 2010; 49:2851-8. [DOI: 10.1021/ic902341w] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jean-Daniel Compain
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin, 78035 Versailles Cedex, France
| | - Pierre Mialane
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin, 78035 Versailles Cedex, France
| | - Anne Dolbecq
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin, 78035 Versailles Cedex, France
| | - Israël Martyr Mbomekallé
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin, 78035 Versailles Cedex, France
| | - Jérôme Marrot
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin, 78035 Versailles Cedex, France
| | - Francis Sécheresse
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin, 78035 Versailles Cedex, France
| | - Carole Duboc
- Université Joseph Fourier Grenoble 1/CNRS, Département de Chimie Moléculaire, UMR 5250, Institut de Chimie Moléculaire de Grenoble, FR-CNRS-2607, BP 53, 38041 Grenoble Cedex 9, France
| | - Eric Rivière
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR 8182, Equipe Chimie Inorganique, Univ. Paris-Sud, 91405 Orsay cedex, France
| |
Collapse
|
45
|
Neese F, Ames W, Christian G, Kampa M, Liakos DG, Pantazis DA, Roemelt M, Surawatanawong P, Shengfa Y. Dealing with Complexity in Open-Shell Transition Metal Chemistry from a Theoretical Perspective: Reaction Pathways, Bonding, Spectroscopy, And Magnetic Properties. ADVANCES IN INORGANIC CHEMISTRY 2010. [DOI: 10.1016/s0898-8838(10)62008-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
46
|
Pantazis DA, Krewald V, Orio M, Neese F. Theoretical magnetochemistry of dinuclear manganese complexes: broken symmetry density functional theory investigation on the influence of bridging motifs on structure and magnetism. Dalton Trans 2010; 39:4959-67. [DOI: 10.1039/c001286f] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|