76
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Sharma RP, Saini A, Monga D, Venugopalan P, Jezierska J, Ozarowski A, Ferretti V. Influence of nitrogen donor ligands on the coordination modes of copper(ii) 2-nitrobenzoate complexes: structures, DFT calculations and magnetic properties. NEW J CHEM 2014. [DOI: 10.1039/c3nj00736g] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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77
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Feng X, Mathonière C, Jeon IR, Rouzières M, Ozarowski A, Aubrey ML, Gonzalez MI, Clérac R, Long JR. Tristability in a Light-Actuated Single-Molecule Magnet. J Am Chem Soc 2013; 135:15880-4. [DOI: 10.1021/ja407332y] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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78
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Reger DL, Pascui AE, Pellechia PJ, Ozarowski A. NMR Investigations of Dinuclear, Single-Anion Bridged Copper(II) Metallacycles: Structure and Antiferromagnetic Behavior in Solution. Inorg Chem 2013; 52:12741-8. [DOI: 10.1021/ic402016m] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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79
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Schweinfurth D, Krzystek J, Schapiro I, Demeshko S, Klein J, Telser J, Ozarowski A, Su CY, Meyer F, Atanasov M, Neese F, Sarkar B. Electronic Structures of Octahedral Ni(II) Complexes with “Click” Derived Triazole Ligands: A Combined Structural, Magnetometric, Spectroscopic, and Theoretical Study. Inorg Chem 2013; 52:6880-92. [DOI: 10.1021/ic3026123] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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80
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Tran BL, Krzystek J, Ozarowski A, Chen CH, Pink M, Karty JA, Telser J, Meyer K, Mindiola DJ. Formation and Reactivity of the Terminal Vanadium Nitride Functionality. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201300178] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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81
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Moomaw EW, Hoffer E, Moussatche P, Salerno J, Grant M, Immelman B, Uberto R, Ozarowski A, Angerhofer A. Kinetic and Spectroscopic Studies of Bicupin Oxalate Oxidase and Putative Active Site Mutants. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.789.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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82
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Ponomaryov AN, Kim N, Hwang J, Nojiri H, van Tol J, Ozarowski A, Park J, Jang Z, Suh B, Yoon S, Choi KY. Structural Tailoring Effects on the Magnetic Behavior of Symmetric and Asymmetric Cubane-Type Ni complexes. Chem Asian J 2013; 8:1152-9. [DOI: 10.1002/asia.201300054] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Indexed: 11/10/2022]
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83
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Moomaw EW, Hoffer E, Moussatche P, Salerno JC, Grant M, Immelman B, Uberto R, Ozarowski A, Angerhofer A. Kinetic and spectroscopic studies of bicupin oxalate oxidase and putative active site mutants. PLoS One 2013; 8:e57933. [PMID: 23469254 PMCID: PMC3585803 DOI: 10.1371/journal.pone.0057933] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 01/29/2013] [Indexed: 01/02/2023] Open
Abstract
Ceriporiopsis subvermispora oxalate oxidase (CsOxOx) is the first bicupin enzyme identified that catalyzes manganese-dependent oxidation of oxalate. In previous work, we have shown that the dominant contribution to catalysis comes from the monoprotonated form of oxalate binding to a form of the enzyme in which an active site carboxylic acid residue must be unprotonated. CsOxOx shares greatest sequence homology with bicupin microbial oxalate decarboxylases (OxDC) and the 241-244DASN region of the N-terminal Mn binding domain of CsOxOx is analogous to the lid region of OxDC that has been shown to determine reaction specificity. We have prepared a series of CsOxOx mutants to probe this region and to identify the carboxylate residue implicated in catalysis. The pH profile of the D241A CsOxOx mutant suggests that the protonation state of aspartic acid 241 is mechanistically significant and that catalysis takes place at the N-terminal Mn binding site. The observation that the D241S CsOxOx mutation eliminates Mn binding to both the N- and C- terminal Mn binding sites suggests that both sites must be intact for Mn incorporation into either site. The introduction of a proton donor into the N-terminal Mn binding site (CsOxOx A242E mutant) does not affect reaction specificity. Mutation of conserved arginine residues further support that catalysis takes place at the N-terminal Mn binding site and that both sites must be intact for Mn incorporation into either site.
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84
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Jiang P, Li J, Ozarowski A, Sleight AW, Subramanian MA. Intense Turquoise and Green Colors in Brownmillerite-Type Oxides Based on Mn5+ in Ba2In2–xMnxO5+x. Inorg Chem 2013; 52:1349-57. [DOI: 10.1021/ic3020332] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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85
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Nesterova OV, Chygorin EN, Kokozay VN, Bon VV, Omelchenko IV, Shishkin OV, Titiš J, Boča R, Pombeiro AJL, Ozarowski A. Magnetic, high-field EPR studies and catalytic activity of Schiff base tetranuclear CuII2FeIII2 complexes obtained by direct synthesis. Dalton Trans 2013; 42:16909-19. [PMID: 24091798 DOI: 10.1039/c3dt51800k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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86
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Forshaw AP, Smith JM, Ozarowski A, Krzystek J, Smirnov D, Zvyagin SA, Harris TD, Karunadasa HI, Zadrozny JM, Schnegg A, Holldack K, Jackson TA, Alamiri A, Barnes DM, Telser J. Low-Spin Hexacoordinate Mn(III): Synthesis and Spectroscopic Investigation of Homoleptic Tris(pyrazolyl)borate and Tris(carbene)borate Complexes. Inorg Chem 2012; 52:144-59. [DOI: 10.1021/ic301630d] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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87
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Jackson TA, Krzystek J, Ozarowski A, Wijeratne GB, Wicker BF, Mindiola DJ, Telser J. Vanadocene de Novo: Spectroscopic and Computational Analysis of Bis(η5-cyclopentadienyl)vanadium(II). Organometallics 2012. [DOI: 10.1021/om300892y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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88
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Senchyk GA, Lysenko AB, Rusanov EB, Chernega AN, Jezierska J, Domasevitch KV, Ozarowski A. Structure and Magnetic Behavior of CuIIMOFs Supported by 1,2,4-Triazolyl-Bifunctionalized Adamantane Scaffold. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200873] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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89
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Reger DL, Pascui AE, Smith MD, Jezierska J, Ozarowski A. Dinuclear Complexes Containing Linear M–F–M [M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II)] Bridges: Trends in Structures, Antiferromagnetic Superexchange Interactions, and Spectroscopic Properties. Inorg Chem 2012; 51:11820-36. [DOI: 10.1021/ic301757g] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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90
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Nesterov DS, Chygorin EN, Kokozay VN, Bon VV, Boča R, Kozlov YN, Shul’pina LS, Jezierska J, Ozarowski A, Pombeiro AJL, Shul’pin GB. Heterometallic CoIII4FeIII2 Schiff Base Complex: Structure, Electron Paramagnetic Resonance, and Alkane Oxidation Catalytic Activity. Inorg Chem 2012; 51:9110-22. [PMID: 22853695 DOI: 10.1021/ic301460q] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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91
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Reger DL, Pascui AE, Smith MD, Jezierska J, Ozarowski A. Halide and Hydroxide Linearly Bridged Bimetallic Copper(II) Complexes: Trends in Strong Antiferromagnetic Superexchange Interactions. Inorg Chem 2012; 51:7966-8. [DOI: 10.1021/ic301321r] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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92
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Tran BL, Pinter B, Nichols AJ, Konopka FT, Thompson R, Chen CH, Krzystek J, Ozarowski A, Telser J, Baik MH, Meyer K, Mindiola DJ. A Planar Three-Coordinate Vanadium(II) Complex and the Study of Terminal Vanadium Nitrides from N2: A Kinetic or Thermodynamic Impediment to N–N Bond Cleavage? J Am Chem Soc 2012; 134:13035-45. [DOI: 10.1021/ja303360v] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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93
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Tucker PC, Nyffeler J, Chen B, Ozarowski A, Stillwell R, Latturner SE. A Tale of Two Metals: New Cerium Iron Borocarbide Intermetallics Grown from Rare-Earth/Transition Metal Eutectic Fluxes. J Am Chem Soc 2012; 134:12138-48. [PMID: 22731682 DOI: 10.1021/ja303370j] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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94
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Choi KY, Wang Z, Ozarowski A, van Tol J, Zhou HD, Wiebe CR, Skourski Y, Dalal NS. Spin dynamics of the S = 5/2 2D triangular antiferromagnet Ba3NbFe3Si2O14. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:246001. [PMID: 22627202 DOI: 10.1088/0953-8984/24/24/246001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report pulse-field magnetization, ac susceptibility, and 100 GHz electron spin resonance (ESR) measurements on the S = 5/2 two-dimensional triangular compound Ba3NbFe3Si2O14 with the Néel temperature T(N) = 26 K. The magnetization curve shows an almost linear increase up to 60 T with no indication of a one-third magnetization plateau. An unusually large frequency dependence of the ac susceptibility in the temperature range of T = 20-100 K reveals a spin-glass behavior or superparamagnetism, signaling the presence of frustration-related slow magnetic fluctuations. The temperature dependence of the ESR linewidth exhibits two distinct critical regimes; (i) ΔH(pp)(T) is proportional to (T-T(N))(-p) with the exponent p = 0.2(1)-0.2(3) for temperatures above 27 K, and (ii) ΔH(pp)(T) is proportional to (T-T*)(-p) with T* = 12 K and p = 0.8(1)-0.8(4) for temperatures between 12 and 27 K. This is interpreted as indicating a dimensional crossover of magnetic interactions and the persistence of short-range correlations with a helically ordered state.
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95
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Krzystek J, Ozarowski A, Zvyagin SA, Telser J. High Spin Co(I): High-Frequency and -Field EPR Spectroscopy of CoX(PPh3)3 (X = Cl, Br). Inorg Chem 2012; 51:4954-64. [DOI: 10.1021/ic202185x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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96
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Desrochers PJ, Sutton CA, Abrams ML, Ye S, Neese F, Telser J, Ozarowski A, Krzystek J. Electronic Structure of Nickel(II) and Zinc(II) Borohydrides from Spectroscopic Measurements and Computational Modeling. Inorg Chem 2012; 51:2793-805. [DOI: 10.1021/ic201775c] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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97
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Telser J, Ozarowski A, Krzystek J. High-frequency and -field electron paramagnetic resonance of transition metal ion (d block) coordination complexes. ELECTRON PARAMAGNETIC RESONANCE 2012. [DOI: 10.1039/9781849734837-00209] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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98
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Reger DL, Debreczeni A, Smith MD, Jezierska J, Ozarowski A. Copper(II) Carboxylate Dimers Prepared from Ligands Designed to Form a Robust π···π Stacking Synthon: Supramolecular Structures and Molecular Properties. Inorg Chem 2011; 51:1068-83. [DOI: 10.1021/ic202198k] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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99
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Zorko A, Pregelj M, Potočnik A, van Tol J, Ozarowski A, Simonet V, Lejay P, Petit S, Ballou R. Role of antisymmetric exchange in selecting magnetic chirality in Ba3NbFe3Si2O14. PHYSICAL REVIEW LETTERS 2011; 107:257203. [PMID: 22243107 DOI: 10.1103/physrevlett.107.257203] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Indexed: 05/31/2023]
Abstract
We present an electron spin resonance (ESR) investigation of the acentric Ba(3)NbFe(3)Si(2)O(14), featuring a unique single-domain double-chiral magnetic ground state. Combining simulations of the ESR linewidth anisotropy and the antiferromagnetic-resonance modes allows us to single out the Dzyaloshinsky-Moriya (DM) interaction as the leading magnetic anisotropy term. We demonstrate that the rather minute out-of-plane DM component d(c)=45 mK is responsible for selecting a unique ground state, which endures thermal fluctuations up to astonishingly high temperatures.
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100
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Krzystek J, Smirnov D, Schlegel C, van Slageren J, Telser J, Ozarowski A. High-frequency and -field EPR and FDMRS study of the [Fe(H2O)6]2+ ion in ferrous fluorosilicate. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 213:158-165. [PMID: 22015248 DOI: 10.1016/j.jmr.2011.09.046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 08/24/2011] [Accepted: 09/23/2011] [Indexed: 05/31/2023]
Abstract
The complex [Fe(H2O)6]SiF6 is one of the most stable and best characterized high-spin Fe(II) salts and as such, is a paradigm for the study of this important transition metal ion. We describe high-frequency and -field electron paramagnetic resonance studies of both pure [Fe(H2O)6]SiF6 and [Zn(H2O)6]SiF6 doped with 8% of Fe(II). In addition, frequency domain magnetic resonance spectroscopy was applied to these samples. High signal-to-noise, high resolution spectra were recorded which allowed an accurate determination of spin Hamiltonian parameters for Fe(II) in each of these two, related, environments. For pure [Fe(H2O)6]SiF6, the following parameters were obtained: D=+11.95(1) cm(-1), E=0.658(4) cm(-1), g=[2.099(4),2.151(5),1.997(3)], along with fourth-order zero-field splitting parameters: B4(0)=17(1)×10(-4) cm(-1) and B4(4)=18(4)×10(-4) cm(-1), which are rarely obtainable by any technique. For the doped complex, D=+13.42(1) cm(-1), E=0.05(1) cm(-1), g=[2.25(1),2.22(1),2.23(1)]. These parameters are in good agreement with those obtained using other techniques. Ligand-field theory was used to analyze the electronic absorption data for [Fe(H2O)6]SiF6 and suggests that the ground state is 5A1, which allows successful use of a spin Hamiltonian model. Density functional theory and unrestricted Hartree-Fock calculations were performed which, in the case of latter, reproduced the spin Hamiltonian parameters very well for the doped complex.
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