Dr. Thomas Weyhermüller - Chemical Synthesis, X-ray structure analysis

Dr. Thomas Weyhermüller
Leiter der Gruppe Chemical Synthesis, X-ray structure analysis
Abteilung Anorganische Spektroskopie

Vita

Diplom (Chemie)Ruhr-Universität Bochum (1989)
Ph.D., wiss. MA
Ruhr-Universität Bochum (1990-1994)
Dr. rer. nat.Ruhr-Universität Bochum (1994)
Gruppenleiter MPI für Bioanorganische Chemie; heute: MPI CEC (since 1995)

Publikationen

Download: Publikationsliste (.pdf)

Link: Researcher ID
Link: ORCID

2019

  • Kalläne, S.I., Hahn, A.W., Weyhermüller, T., Bill, E., Neese, F., DeBeer, S., van Gastel, M. (2019). Spectroscopic and Quantum Chemical Investigation of Benzene-1,2- dithiolate-Coordinated Diiron Complexes with Relevance to Dinitrogen Activation Inorganic Chemistry https://doi.org/10.1021/acs.inorgchem.9b00177
  • Bhand, S., Landem D.N., Pereira, E., Gejji, S.P., Weyhermüller, T., Chakravarty, D., Puranik, V.G., Salunke-Gawali, S. (2019). Amphiphilic polypyridyl ruthenium complexes: Synthesis, Characterization and Aggregation studies Polyhedron 164, 96-107. https://doi.org/10.1016/j.poly.2019.02.035
  • Römelt, C., Weyhermüller, T., Wieghardt, K. (2019). Structural characteristics of redox-active pyridine-1,6-diimine complexes: Electronic structures and ligand oxidation levels Coordination Chemistry Reviews 380, 287-317. https://doi.org/10.1016/j.ccr.2018.09.018
  • Wang, M., Römelt, C., Weyhermüller, T., Wieghardt, K. (2019). Coordination Modes, Oxidation, and Protonation Levels of 2,6-Pyridinediimine and 2,2′:6′,2′́-Terpyridine Ligands in New Complexes of Cobalt, Zirconium, and Ruthenium. An Experimental and Density Functional Theory Computational Study Inorganic Chemistry 58(1), 121-132. https://doi.org/10.1021/acs.inorgchem.8b01949

2018

  • Erken, C., Kaithal, A., Sen, S., Weyhermüller, T., Hölscher, M., Werlé, C., Leitner, W. (2018). Manganese-catalyzed hydroboration of carbon dioxide and other challenging carbonyl groups Nature Communications, 9, 4521. https://doi.org/10.1038/s41467-018-06831-9
  • Kundu, S., Dutta, D., Maity, S., Weyhermüller, T., Ghosh, P. (2018). Proton-Coupled Oxidation of a Diarylamine: Amido and Aminyl Radical Complexes of Ruthenium(II) Inorganic Chemistry, 57(19), 11948-11960. https://doi.org/10.1021/acs.inorgchem.8b01401
  • Levin, N., Codesido N.O., Marcolongo, J.P., Alborés, Weyhermüller, T., Olabe, J.A., Slep, L.D. (2018). Remarkable Changes of the Acidity of Bound Nitroxyl (HNO) in the [Ru(Me3[9]aneN3)(L2)(NO)]n+ Family (n = 1–3). Systematic Structural and Chemical Exploration and Bioinorganic Chemistry Implications Inorganic Chemistry, 57(19), 12270-12281. https://doi.org/10.1021/acs.inorgchem.8b01958
  • Hahn, A.W., Van Kuiken, B.E., Chilkuri, V.G., Levin, N., Bill, E., Weyhermüller, T., Nicolaou, A., Miyawaki, J., Harada, Y., DeBeer, S. (2018). Probing the Valence Electronic Structure of Low-Spin Ferrous and Ferric Complexes Using 2p3d Resonant Inelastic X‑ray Scattering (RIXS) Inorganic Chemistry, 57(37), 11918-11923. https://doi.org/10.1021/acs.inorgchem.8b01550
  • Van Kuiken, B.E., Hahn, A.W., Nayyar, B., Schiewer, C.E., Lee, S.C., Meyer, F., Weyhermüller, T., Nicolaou, A., Cui, Y-T., Miyawaki, J., Hatada, Y., DeBeer, S. (2018). Electronic Spectra of Iron-​Sulfur Complexes Measured by 2p3d RIXS Spectroscopy Inorganic Chemistry, 57(12), 7355-7361. https://doi.org/10.1021/acs.inorgchem.8b01010
  • Römelt, C., Weyhermüller, T., van Gastel, M.,  Bill, E.,  Ye, S., Neese, F. (2018)
    The Electronic Structure and Spin Multiplicity of Iron Tetraphenylporphyrins in Their Reduced States as Determined by a Combination of Resonance Raman Spectroscopy and Quantum Chemistry Inorganic Chemistry, 57(37), 2141-2148.

2017

  • J.A. Rees, R. Bjornsson, J.K. Kowalska, F.A. Lima, J. Schlesier, D. Sippel, T. Weyhermüller, O. Einsle, J.A. Kovacs, S. DeBeer: Comparative Electronic Structures of Nitrogenase FeMoco and FeVco. Dalton Trans. 2017, 46, 2445-2455 
  • E.A. Suturina, J. Nehrkorn, J.M. Zadrozny, S. Hill, J. Liu, M. Atanasov, T. Weyhermüller, D. Maganas, A. Schnegg, E. Bill, J.R. Long, F. Neese: Magneto-Structural Correlations in Pseudo-Tetrahedral [CoII(SPh)4]2- Complexes: Magnetometry, MCD, Advanced EPR and Ab Initio Study Inorg. Chem. 2017, 56, 3102–3118 
  • A.R. Chowdhury, B.G. Roy, S. Jana, T. Weyhermüller, P. Banerjee: A simple cleft shaped hydrazine-functionalized colorimetric new Schiff base chemoreceptor for selective detection of F− in organic solvent through PET signaling: Development of a chemoreceptor based sensor kit for detection of fluoride. Sensors & Actuators 2017, B241, 706-715 
  • C. Römelt, J. Song, M. Tarrago, T. Weyhermüller, S. DeBeer, E. Bill, F. Neese, S. Ye: Electronic Structure of a Formal Iron(0) Porphyrin Complex Relevant to CO2 Reduction. Inorg. Chem. 2017, 56, 4746-4751 
  • M.V. Manickavasagar, M. Thangaraju, T. Weyhermüller, P. Velmurugan, N. Murthy N, B.U. Nair: Novel mononuclear Cu(II) terpyridine complexes: Impact of fused ring thiophene and thiazole head groups towards DNA/BSA interaction, cleavage and antiproliferative activity on triple negative CAL-51 cell line. Eur. J. Med. Chem. 2017, 135, 434-446 
  • G. Sabenya, L. Lázaro, I. Gamba, V. Martin-Diaconescu, E. Andris, T. Weyhermüller, F. Neese, J. Roithova, E. Bill, J. Lloret-Fillol, M. Costas: Generation, Spectroscopic and Chemical Characterization of an Octahedral Iron(V)–Nitrido Species with a Neutral Ligand Platform J. Am. Chem. Soc. 2017,139, 9168-9177 
  • A.W. Hahn, B.E. Van Kuiken, M. al Samarai, M. Atanasov. T. Weyhermüller, Yi-Tao Cui, J. Miyawaki, y. Harada, A. Nicolaou. S. DeBeer: Measurement of the Ligand Field Spectra of Ferrous and ferric Iron Chlorides Using 2p3d RIXS. Inorg. Chem. 2017, 56, 8203-8211
  • J.K. Kowalska, B. Nayyar, J.A. Rees, C.E.Schiewer, S.C. Lee, J.A. Kovacs, F. Meyer, T. Weyhermüller, E. Otero, S. DeBeer: Iron L2,3-edge X-ray Absorption and X-ray Magnetic Circular Dichroism Studies of Molecular Iron Complexes with Relevance to the FeMoco and FeVco Active Sites of Nitrogenase. Inorg. Chem. Inorg. Chem. 2017, 56, 8147-8158 
  • M. Khannam, T. Weyhermüller, U. Goswami, C. Mukherjee: A Highly Stable L-Alanine-Based Mono(aquated) Mn(II) Complex as T1-weighted MRI Contrast Agent. Dalton Trans. 2017, 46, 10426-10432 
  • T. Weyhermüller, S. Bera, S. Maity, M. Shit, P. Ghosh: Coordination of o-benzosemiquinonate, o-iminobenzo-semiquinonate and imine anion radicals to oxidovanadium(IV) New J. Chem. 2017, 41, 4564-4572
  • Levin, N., Perdomenico, J., Bill, E., Weyhermüller, T., Slep, L.: Pushing the photodelivery of nitric oxide to the visible: Are {FeNO}7 complexes good candidates? Dalton Trans. 2017, 46, 16058-16064

2016

  • S. Bera, M. Shit, S. Maity, S. Maji, T. Weyhermüller, P. Ghosh: Oxidovanadium Complexes of 2,2′-Bipyridine, 1,10 Phenanthronline and p-Nitro-o-aminophenol - Radical versus Nonradical States. Eur. J. Inorg. Chem. 2016, 330-338
  • S. Bera, S.Maity, T. Weyhermüller, P. Ghosh: Radical non radical states of the [Ru(PIQ)] core in complexes (PIQ = 9,10-phenathreneiminoquinone). Dalton Trans. 2016, 45, 8236-8247
  • S. Bera, S. Mondal, S. Maity, T. Weyhermüller, P. Ghosh: Radical Non-radical States of the [Os(PIQ)] Core (PIQ = 9,10-Phenanthreneiminoquinone): Iminosemiquinone to Iminoquinone Conversion Promoted o-Metalation Reaction. Inorg. Chem. 2016, 55, 4746-4757
  • M. Wang, T. Weyhermüller, E. Bill, K. Wieghardt, S. Ye: Structural and Spectroscopic Characterization of Rhenium Complexes Containing Neutral, Mono-, and Dianionic Ligands of  2,2’-Bipyridines and 2,2’:6,2’’-Terpyridines. An Experimental and Density Functional Theory (DFT)-Computational Study. Inorg. Chem. 2016, 55, 5019-5036
  • U.A. Dar,S. Bhand, D.N. Lande, S.S. Rao, Y.P. Patil, S.P. Gejji, M. Nathaji, T. Weyhermüller, S. Salunke-Gawali: Molecular Structures of 2-hydroxy-1,4-naphthoqinone derivatives and their Zinc(II) complexes : Combining Experiment and Density Functional Theory.
    Polyhedron 2016, 113, 61-72
  • S. Bhand, R. Patil, Y. Shinde, D.N. Lande, S.S. Rao, L. Kathawate, S.P. Gejji, T. Weyhermüller, S. Salunke-Gawali: Tautomerism in o-Hydroxyanilino-1,4-naphthoquinone Derivatives: Structure, NMR, HPLC and Density Functional Theoretic Iinvestigation. J. Mol. Struct. 2016, 1123, 245-260
  • S. Kundu, A. Mondal, T. Weyhermüller, S. Sproules, P. Ghosh: Molecular and Electronic Structures of Copper-Cuprizone and Analogues. Inorg. Chim. Acta 2016, 451, 23-30
  • S. Maity, S. Kundu, S. Bera, T. Weyhermüller, P. Ghosh: Mixed-Valence o-Iminobenzoquinone and o-Iminobenzosemiquinonate Anion Radical Complexes of Cobalt: Valence Tautomerism. Eur. J. Inorg. Chem. 2016, 3680-3690
  • S. Maity, S. Kundu, S. Bera, T. Weyhermüller, P. Ghosh: o-Iminobenzoquinone and o-Iminobenzosemiquinonate Anion Radical Complexes of Rhodium and Ruthenium. Eur. J. Inorg. Chem. 2016, 3691-3697
  • N. Levin Rojas, N. Osa Codesido, E. Bill, T. Weyhermüller, A. Gaspari, R. Santana da Silva, J. Olabe, L. Slep: Structural, spectroscopic and photochemical investigation of an octahedral NO releasing {RuNO}7 species. Inorg. Chem. 2016, 55, 7808-7810
  • S. Maity, M. Shit,  S. Bera, T. Weyhermüller, P. Ghosh: Coordination of o-benzosemiquinonate, o-iminobenzosemiquinonate, 4,4'-di-tert-butyl-2,2'-bipyridine and 1,10-phenanthroline anion radicals to oxidovanadium(IV). New J. Chem. 2016, 40, 10305-10315
  • S. Bera, S. Maity, T. Weyhermüller, P. Ghosh: Arylamino radical complexes of ruthenium and osmium: dual radical counter in a molecule. Dalton Trans. 2016, 45, 19428-19440

2015

  • R. Bjornsson, M.U. Delgado-Jaime, F.A. Lima, D. Sippel, J. Schlesier, T. Weyhermüller, O. Einsle, F. Neese, S. DeBeer: Mo L-Edge Spectra of MoFe Nitrogenase.
    Z. Anorg. Allg. Chem. 2015, 65-71
  • M. Wang, T. Weyhermüller, K. Wieghardt: Determining the Electronic Structure of a Series of [(phen)3M]0 (M = Ti, V, Mo) and [(pdi)2M]n+ (M = Cr, Mo) Complexes: Neutral Ligands vs. p-Radical Anions. Eur. J. Inorg. Chem. 2015, 3246-3254
  • S. Chaudhuri, S. Kundu, M.K. Biswas,T. Weyhermüller, P. Ghosh: Mononuclear Zinc(II), Cadmium(II), Cobalt(III) and Di-nuclear Nickel(II) Complexes of a 14 Electron Diimine Ligand: Syntheses, Structures, Photoluminescence and DFT Investigations .
    Inorg. Chim. Acta 2015, 430, 199-207
  • P. Ghosh, S. Maity, S. Kundu, T.Weyhermüller, A. Roy: Orthometallation of Dibenzo[1,2]quinoxaline with Ruthenium(II/III), Osmium(II/III/IV) and Rhodium(III) Ions and Orthometallated [RuNO]6/7 Derivatives. Inorg. Chem. 2015, 54, 1384-1394
  • D. Chadar, M. Camilles, A. Khan, T. Weyhermüller, S. Salunke-Gawali: Synthesis and characterization of n-alkylamino derivatives of vitamin K3: Molecular structure of 2-methyl-3-(n-propylamino)-1,4-naphthoquinone and antibacterial activities. J. Mol. Struct. 2015, 179-189
  • S. Maity, S. Kundu, T. Weyhermuller, P. Ghosh: Tris 2,2′-Azobispyridine Complexes of Copper(II): X-ray Structures, Reactivities and the Radical Non-Radical bis Analogues.
    Inorg. Chem. 2015, 54, 1300-1313
  • J.P. Marcolongo, T. Weyhermüller and L.D. Slep: Exploring the Photo-stability of the {Ru(py)4}2+ Fragment. Inorg. Chim. Acta 2015, 429, 174-182
  • A.P. Ware, A. Patil, S. Klomane, S.S. Pingale, T. Weyhermüller, S. Salunke-Gawali: Naphthoquinone based chemosensor 2-(2'-aminomethylpyridine)-3-chloro-1,4-naphthoquinone for metal ions: Single crystal X-ray structure, experimental and TD-DFT study. J. Mol. Struct. 2015, 1093, 39-48
  • M. Wang, J. England, T. Weyhermüller, K. Wieghardt: Electronic Structures of “low valent” Neutral Complexes [NiL2]0 (S = 0) (L = bpy, phen, tpy): An Experimental and DFT Computational Study. Eur. J. Inorg. Chem. 2015, 1511-1523
    Kochem, T. Weyhermüller, F. Neese, M. van Gastel: EPR and Quantum Chemical Investigation of a Bioinspired Hydrogenase Model with a Redox Active Ligand in the First Coordination Sphere. Organometallics 2015, 34, 995-1000
    K. Weber, T. Weyhermüller, E. Bill, Ö.F. Erdem, W. Lubitz: Design and Characterization of Phosphine Iron Hydrides: Towards Hydrogen Producing Catalysts.
    Inorg. Chem. 2015, 54, 6928-6937
  • D. Chadar, S.S. Rao, A. Khan, S.P. Gejji, K.S. Bhat, T. Weyhermüller, S. Salunke-Gawali:
    Benzo[α]phenoxazines and Benzo[α]phenothiazine from Vitamin K3: Synthesis, Molecular Structures, DFT Studies and Cytotoxic Activity. RSC Adv. 2015, 5, 57917-57929
  • S. Pal, V.B. Konkimalla, L.Kathawate, S.S. Rao, S.P. Gejii, V.G. Puranik, T.Weyhermüller, S. Salunke-Gawali: Targeting chemorefractory COLO205 (BRAF V600E) cell lines using substituted benzo[]phenoxazines. RSC Advances 2015, 82549-82263
  • L. Maxwell, S. Gómez-Coca, T. Weyhermüller, D. Panyella, E. Ruiz: A Trinuclear Cu(II) Complex with Functionalized s-Heptazine N-ligands: Molecular Chemistry from a g-C3N4 Fragment.
    Dalton Trans. 2015, 44, 15761-15763
  • L. Rapatskiy, W. Ames, M. Perez Navarro, A. Savitsky, J. Griese, T. Weyhermüller, H. Shafaat, M. Högbom, F. Neese, D. Pantazis, N. Cox: Characterization of Oxygen Bridged Manganese Model Complexes Using Multifrequency 17O-Hyperfine EPR Spectroscopies and Density Functional Theory. J. Phys. Chem. 2015, 119, 13904-13921
  • J. England, E. Bill, T. Weyhermüller, F. Neese, M. Atanasov, K. Wieghardt: Molecular Structures of Homoleptic Six-Coordinate Cobalt(I) Complexes of 2,2’:6,2’’-Terpyridine, 2,2’-Bipyridine, and 1,10-Phenanthroline. An Experimental and Computational Study.
    Inorg. Chem. 2015, 54, 12002-12018

2014

  • R. Bjornsson, F.A. Lima, T. Weyhermüller, P. Glatzel, T. Spatzal, O. Einsle, E. Bill, F. Neese, S. DeBeer: Identification of a spin-coupled Mo(III) in the Nitrogenase Iron-Molybdenum Cofactor
    Chem. Sci. 2014, 5, 3096-3103
  • K.S. Pedersen, M. Sigrist, M.A. Sörensen, A.L. Barra, T. Weyhermüller, S. Piligkos, C.A.Thuesen, M.G. Vinum, H. Mutka, H. Weihe, R. Clearc, J. Bendix:  [ReF6]2-: A Robust Module for the Design of Molecule-Based Magnetic Materials. Angew. Chem. Int. Ed. 2014, 53, 1351-1354
  • K. Weber, Ö.F. Erdem, E. Bill, T. Weyhermüller, W. Lubitz: Modeling the Active Site of [NiFe]-Hydrogenases and the [NiFeu] Subsite of the C-Cluster of Carbon Monoxide Dehydrogenases: Low-Spin Iron(II) Versus High Spin Iron(II). Inorg. Chem. 2014, 53, 6329-6337
  • M. Wang, T. Weyhermüller, K. Wieghardt: The Electron Transfer Series [Mo(bpy)3]n (n = 3+, 2+, 1+, 0, 1-), and the Dinuclear Species [{MoCl(Mebpy)2}2(µ2-O)]Cl2 and [{MoIV(tpy)2}2(µ2-MoO4)](PF6)2•4MeCN. Chem. Eur. J. 2014, 20, 9037-9044
  • M. Wang, E. Bill, T. Weyhermüller, K. Wieghardt: The Neutral Complex [CrIII43-O)22-CH3CO2)7(tbpy0)(tbpy•)]0 - A Tetranuclear Cr(III) Species Containing a Neutral (bpy0) and a π-Radical Anion (bpy•)1-. Can. J. Chem. 2014, 92, 913-917
  • C. Plenk, T. Weyhermüller,  E. Rentschler: Folded Cr12Co12 and Cr12Ni12 Wheels: A Sharp Increase in Nuclearity of Heterometallic Chromium Rings. Chem. Commun. 2014, 50, 3871-3873
  • D. Maganas, M. Roemelt, T. Weyhermüller, R. Blume, M. Hävecker, A. Knop Gericke, S. DeBeer, R. Schlögl, F. Neese: L-Edge X-Ray Absorption Study of Mononuclear Vanadium Complexes and Spectral Predictions Using a Restricted Open Shell Configuration Interaction Ansatz. Phys. Chem. Chem. Phys. 2014, 16, 264-276
  • K. Weber, I. Heise, T. Weyhermüller, W. Lubitz: Synthesis and characterization of nickel compounds with tetradentate thiolate-thioether ligands as precursors for [NiFe] hydrogenase models. Eur. J. Inorg. Chem. 2014, 148-155
  • S. Salunke-Gawali, O. Pawar, M. Nikalje, R. Patil, T. Weyhermüller, V.G. Puranik , V.B. Konkimalla: Synthesis, characterization and molecular structures of homologated analogs of 2-bromo-3-(n-alkylamino)-1,4-napthoquinone. J. Mol. Struct. 2014, 1056-1057, 97-103
  • N. Osa Codesido, T. Weyhermüller, J.A. Olabe, L. Slep: Nitrosyl-Centered Redox and Acid-Base Interconversions in [Ru(Me3[9]aneN3)(bpy)(NO)]3,2,1+. The pKa of Bound HNO in Aqueous Solution. Inorg. Chem. 2014, 53, 981-997
  • M. Wang, J. England, T. Weyhermüller, K. Wieghardt: Molecular and Electronic Structures of the Members of the Electron Transfer Series [Mn(bpy)3]n (n = 2+, 1+, 0, 1–) and [Mn(tpy)2]m (m = 4+, 3+, 2+, 1+, 0). An Experimental and Density Functional Theory Study. Inorg. Chem. 2014, 53, 2276-2287
  • K.S. Pedersen, G. Lorusso, J.J. Morales, T. Weyhermüller, S. Piligkos, S.K. Singh, M. Schau-Magnussen,G. Rajaraman, M. Evangelisti, J. Bendix: Fluoride-bridged {GdIII3MIII2} (M=Cr, Fe, Ga) Molecular Magnetic Refrigerants. Angew. Chemie Int. Ed. 2014, 53, 2394-2397
  • S.C. Patra, T. Weyhermüller, P. Ghosh: Ruthenium, Rhodium, Osmium, and Iridium Complexes of Osazones: Radical versus Non-radical States. Inorg. Chem. 2014, 53, 2427-2440
  • S. Chaudhuri, S. Bera, M.K. Biswas, A.S. Roy, T. Weyhermüller, P. Ghosh:
    Oxidovanadium(IV), oxidomolybdenum(VI) and cobalt(III) complexes of o-phenylenediamine derivatives: oxidative dehydrogenation and photoluminescence. Inorg. Chem. Front. 2014, 1, 331-341
  • L. Kathawate, P.V. Joshi, T.K. Dash, S. Pal, M. Nikalje, T. Weyhermüller, S-Salunke-Gawali: Reaction between lawsone and aminophenol derivatives: Synthesis, Chracterization, Molecular Structures and Antiprolifertive Activity. J. Mol. Struc. 2014, 1075, 397-405
  • R. Patil, D. Chadar, D. Chaudhari, J. Peter, M. Nikalje, T. Weyhermüller, S. Salunke-Gawali: Synthesis and characterization of 2-(n-alkylamino)-1,4-napthoquinone: Molecular structures of ethyl and hexyl derivatives. J. Mol. Struc. 2014, 1075, 345-351
  • B.U. Nair, T. Weyhermüller, V. M. Manikandamathavan, R. P. Parameswari,  M. Sathishkumar,  V. Subramanian: DNA/Protein Interaction and Cytotoxic Activity of Imidazole Terpyridine Derived Cu(II)/Zn(II) Metal Complexes. Dalton Trans 2014, 43, 13018-13031
  • S.C. Patra, A.S. Roy, V.Manivannan, T. Weyhermüller, P. Ghosh: Ruthenium, Osmium and Rhodium complexes of 1,4-diazabutdiene: Radical versus Non-radical States. Dalton. Trans. 2014, 43, 13731-13741
  • P. Saha, A.S. Roy, T. Weyhermüller, P. Ghosh: Metal ion promoted tautomerization and C-N bond cleavage: conversion of catechol to p-benzoquinone derivative.
    Chem. Commun. 2014, 50, 13073-13076

2013

  • Kochem, F. Thomas, O. Jarjayes, G. Gelon, C. Philouze, T. Weyhermüller, F. Neese, M. van Gastel: Structural and Spectroscopic Investigation of an  Anilinosalen Cobalt Complex with Relevance to Hydrogen Production. Inorg. Chem. 2013, 52, 14428-14438
  • F.A. Lima, R. Bjornsson, T. Weyhermüller, P. Chandraskaran, P. Glatzel, F. Neese, S. DeBeer: High-Resolution Molybdenum K-edge X-ray Absorption Spectroscopy Analyzed with Time-Dependent Density Functional Theory. Phys. Chem. Chem. Phys. 2013, 15, 20911-20920
  • S. Hazra, M. Singh, L. Carrella, E. Rentschler, T. Weyhermüller, G. Rajaraman, S. Mohanta: Syntheses, Structures, Magnetic Properties and Density Functional Theoretical Magneto-Structural Correlations of Bis(μ-Phenoxo) and Bis(μ-Phenoxo)-μ-Acetate/ Bis(μ-Phenoxo)-Bis(μ-Acetate) Dinuclear FeIIINiII Compounds. Inorg. Chem. 2013, 52, 12881-12892
  • M. Wang, T. Weyhermüller, J. England, K. Wieghardt: Molecular and Electronic Structures of Six-Coordinate “Low-Valent” [M(Mebpy)3]0 (M = Ti, V, Cr, Mo) and [M(tpy)2]0 (M = Ti, V, Cr), and Seven-Coordinate [MoF(Mebpy)3](PF6) and [MX(tpy)2](PF6) (M = Mo, X = Cl and M = W, X = F). Inorg. Chem. 2013, 52, 12763-12776
  • S. Chaudhuri, S.C. Patra, P.Saha, A.S. Roy, S.Maity, S. Bera, P.S. Sardar, S.Ghosh,P. Ghosh, T. Weyhermüller: Zinc(II), iron(II/III) and ruthenium(II) complexes of o-phenylenediamine derivatives: oxidative dehydrogenation and photoluminescence. Dalton Trans. 2013, 42, 15028-15042
  • Morgenstern, C. Neis, A. Zaschka, J. Romba, T. Weyhermüller, K. Hegetschweiler: Formation and Base Hydrolysis of Oxydimethaneamine Bridges in CoIII-Amine Complexes. Inorg. Chem. 2013, 52, 12080-12097
  • Tondreau, S.C. Stieber, C. Milsmann, E. Lobkovsky, T. Weyhermüller, S. Semproni,
    P. Chirik: Oxidation and Reduction of Bis(imino)pyridine Iron Dinitrogen Complexes: Evidence for Formation of a Chelate Trianion. Inorg. Chem. 2013, 52, 635-646
  • K. Wieghardt. T. Weyhermüller, A. Bowman, S. Sproules, J. England: Electronic Structures of Homoleptic [Tris(2,2’-bipyridine)M]n Complexes of the Early Transition Metals (M = Sc, Y, Ti, Zr, Hf, V, Nb, Ta; n = 1+, 0, 1-, 2-, 3-). An Experimental and Density Functional Theoretical Study. Inorg. Chem. 2013, 52, 2242-2256
  • M. Menelaou, T. Weyhermüller, M. Soler, N. Aliaga Alcalde: Novel Paramagnetic-Luminescent Building Blocks containing Manganese(II) and Anthracene-based Curcuminoids. Polyhedron 2013, 52, 398-405
  • M.K. Biswas, S.C. Patra, A.N. Maity, S.C. Ke, T. Weyhermüller, P. Ghosh: Asymmetric Cleavage of 2,2´-Pyridil to Picolinic Acid Anion Radical Coordinated to Ruthenium(II): Splitting of Water to Hydrogen. Chem. Commun.2013, 49, 4522-4524
  • M. Wang, J. England, T. Weyhermüller, S.  Kokatam, C.J. Pollock, S. DeBeer, J. Shen, G.P.A. Yap, K.H. Theopolt. K. Wieghardt: New Complexes of Chromium(III) Containing Organic -Radical Ligands: An Experimental and DFT Computational Study. Inorg. Chem. 2013, 52, 4472-448
  • J. Arpita, T. Weyhermüller, S. Mohanta: Metal complex analogues of crown ethers as the preorganized motif to stabilize aquated proton in solid state. Cryst. Eng. Comm. 2013, 15, 4099-4106
  • P. Ghosh, M.K. Biswas, T. Weyhermüller, S.C. Patra, A.N. Maity, S.C. Ke: 9,10-Phenanthrenesemiquinone Radical Complexes of Ruthenium(III), Osmium(III) and Rhodium(III) and redox series. Dalton Transactions 2013,  42, 6538-6552
  • S. Kundu, S. Maity, T. Weyhermüller, Prasanta Ghosh: Oxidovanadium Catechol Complexes: Radical versus Non-Radical States and Redox Series. Inorg. Chem. 2013, 52, 7417-7430
  • S. Pal, M. Jadhav, T. Weyhermüller, Y. Patil, M. Nethaji, U. Kasabe, L. Kathawate, V. Badireenath Konkimalla, S. Salunke-Gawali: Molecular Structures and Antiproliferative Activity of Side-Chain Saturated and Homologated Analogs of 2-Chloro-3-(n-alkylamino)-1,4-naphtoquinone. J. Mol. Struc. 2013, 355-361
  • V. Hoeke, E. Krickemeyer, M. Heidemeier, H. Theil, A. Stammler, H. Bögge, T. Weyhermüller, J. Schnack, T. Glaser: A Comprehensive Study on Triplesalen-Based [MnIII6FeIII]3+ and [MnIII6FeII]2+ Complexes: Redox-Induced Variation of Molecular Magnetic properties. Eur. J. Inorg. Chem. 2013, 4398-4409

Publikationen vor 2013 im PDF

Funktionen & Aufgaben

  • since 2000 head of the analytical und preparative GC/HPLC-group

Gruppenmitglieder

Postdocs

  • Dr. Natalia Levin Rojas

Labor

  • Fabian Otto

Chemical synthesis, X-ray structure analysis

Bringing Together Experimental Spectroscopy and Quantum Theory

Chemical activation of inert small molecules like carbon dioxide, methane, nitrogen and others is a key problem in energy research. In the future, energy from renewable sources will be used on a big scale to transform these abundant materials to chemicals for industry and agriculture. Metal catalysts are needed to make such transformations energetically and chemically efficient and selective. We strongly believe that a deep understanding of mechanistic functionality and electronic structure of catalytic systems vastly supports the process of developing better catalysts. It is our approach to combine spectroscopic methods (EPR, MCD, Mössbauer, Resonance Raman, X-Ray methods, etc.) with quantum theory to shine light on the chemical and electronic structure of catalytically active centers. The combination of experiment with theory allows to interpret even very complicated spectroscopic data and to extract the desired chemical information.

Research in my group focuses on the synthesis of metal complexes for spectroscopic investigations. Directed variation of structural and electronic parameters in a series of compounds allows to systematically studying their spectroscopic response. Our samples are typically analyzed by standard methods (elemental analysis, IR, UV/vis, NMR, XRD) before they are further investigated as mentioned above. Such compounds with known molecular structure provide a reliable basis to collect high quality spectroscopic data. In the following, two examples of recent projects are given.

Elucidating the electronic structure of a CO2-reducing catalyst

There are a number of homogenous catalysts known which can reduce carbon dioxide from industrial processes back to valuable chemicals like carbon monoxide, formic acid or formaldehyde. Direct hydrogenation with heterogeneous catalysts can even produce methanol from CO2.  One of the most promising methods to reduce CO2  to useful chemical building blocks is the electrochemical reduction employing an electrocatalyst. Unfortunately, the first reduction step forming the anion radical CO2•−  is at very negative potential and is associated with a huge over potential. Proton coupled reduction is much more favorable in this respect as shown in equation 1.1

eqn. 1 CO2 + e → CO2•−   E°′ = -1.90 V
 
CO2 + 2H+ 2e-→ CO + H2O   E°′ = -0.53 V
CO2 + 2H+ 2e-→ HCO2H   E°′ = -0.61 V
CO2 + 4H+ 4e-→ HCHO + H2O   E°′ = -0.48 V

 

Iron porphyrins have been investigated as potential electrocatalysts for quite some time now. In their super-reduced [(TPP)Fe]2– form - formally a "Fe(0)" state - they are known to act as potent electrocatalysts for CO2 reduction (Fig. 1). The groups of Costentin and Saveant recently added internal proton donor functionalities making the catalyst even more effective.2 There is, however, a lot of controversy on the exact nature of the electronic ground states of [(TPP)Fe]1– and [(TPP)Fe]2–, since the reductions can be either metal or ligand centered. We have therefore started a project to elucidate the electronic structure of these species since we feel that it is crucial to understand the catalytic mechanism to design new and more efficient catalysts.

Preparation of [(TPP)Fe]0/1-/2- species was done by stepwise reduction of [(TPP)Fe IIICl] (1) using the published procedure by Scheidt et al.3 Isolated complexes [(TPP)Fe(THF)2]0 (2) (S = 2), [(TPP)Fe]0 (3) (S = 1), and sodium salts of [(TPP)Fe]1- (4) (S = ½) and [(TPP)Fe]2- (5) (S = 0) were investigated using EPR, resonance Raman, Mössbauer and XAS spectroscopies. Structural parameters of all complexes and their spectroscopic properties were thoroughly calculated using DFT methods. Experimental results clearly evidence that the iron centers in 3, 4 and 5  are of the same, namely intermediate spin Fe(II) character (S=1), which is nicely demonstrated by XAS spectra shown in Figure 2. DFT studies of a hypothetical low spin d7 Fe(I) state for 4 and a low spin d8 Fe(0) state for show that the energy separations between low spin states and intermediate spin states are 188.5 and 47.9 kcal/mol higher in energy for low spin states, far beyond the error range of a DFT calculation. We found that spectroscopic results of the redox series [(TPP)Fe]0/1-/2– only fit with quantum chemical models if the reduction processes are ligand centered, not metal centered. Reduction equivalents are stored in the π*-orbital of the porphyrin ligand to form radical states which are antiferromagnetically coupled to the central intermediate spin iron(II) centers. The porphyrin ligand functions as an electron relay and donates the two electrons necessary to reduce CO2 to CO.

What is the oxidation state of molybdenum in the FeMoco-factor of nitrogenase?

Nitrogenase is a bacterial enzyme which catalyzes the conversion of nitrogen from air to ammonia, an essential source for the biosynthesis of nitrogen containing compounds like peptides or nucleobases. The activation of nitrogen is very challenging since it is probably the most inert small molecule one could think of. A lot has been learned about the chemistry and structure of nitrogenase but the actual exact electronic structure and the catalytic mechanism are still a myth.

One of the two metal containing co-factors in nitrogenase, namely FeMoco, has been identified to be the active site of the enzyme where nitrogen binds and ammonia is released. It is basically composed of seven iron-, a molybdenum-center, nine sulfides, and a light atom, probably interstitial carbide ion. A long debate is going on what the oxidation states of the metal centers are and what the role of molybdenum is. So far, most authors favored Mo(IV) as the oxidation level for the resting state but no final conclusion could be made. We felt challenged to contribute to the solution of this problem and started a project in which we prepared a number of molybdenum model complexes resembling structural features of the natural co-factor. Model complexes and the natural enzyme were investigated using a combined experimental and theoretical approach. High-energy resolution fluorescence detected XAS spectroscopy (HERFD-XAS) was used to analyze complexes and enzyme. This method is superior to normal XAS spectroscopy due to better energy resolution. A detailed computational study in which all meaningful combinations of oxidation states were calculated was performed and results were compared with experimental data. Our analysis shows that the molybdenum atom in FeMoco of Mo-dependent nitrogenase is best described as a Mo(III) coupled to the iron atoms in the cofactor (Figure 3). This is in sharp contrast to the previous description of the molybdenum as a closed-shell Mo(IV).

Crucial to this oxidation state assignment was to utilize HERFD-XAS as well as a direct comparison of the MoFe protein with synthetic [MoFe3S4]3+ model compounds. The electronic structure of the FeMo cofactor, however, is still not fully understood. Understanding the spin coupling between not only the irons but also molybdenum and irons will be an important topic of future studies. Similarly, understanding the effect of the interstitial carbon atom on the electronic structure remains an open question.

Structure Determination

In coordination chemistry structural determination is an absolute prerequisite to understanding properties of transition metal complexes. Furthermore, structure determination by single crystal X-ray diffraction is obligatory in coordination chemistry because our ability to obtain a target compound is limited and unexpected self-assembly phenomena sometimes prevail. X-ray structure analysis delivers highly precise information about the three-dimensional arrangement of atoms, thereby providing bond length and bond angles, which are of enormous importance in understanding chemical properties. Since it is our aim to correlate spectroscopic features and functional properties with structure, X-ray structure analysis is vital to this area of research.

Figure 4 shows a crystal structure from a recent publication in which we studied protonation properties of hydrogenase model complexes.5 Structures of both, unprotonated and protonated species could be determined and the protonation site could be clearly located.

 

References

[1] Benson, E. E.; Kubiak, C. P.; Sathrum, A. J.; Smieja, J. M. Chem. Soc. Rev. 2009, 38, 89-99.

[2] (a) Costentin, C.; Drouet, S.; Passard, G.; Robert, M.; Saveant, J. M. J. Am. Chem. Soc. 2013, 135, 9023-9031. (b) Costentin, C.; Passard, G.; Robert, M.; Saveant, J. M. J. Am. Chem. Soc. 2014, 136, 11821–11829.

[3] Mashiko, T.; Reed, C. A.; Haller, K. J.; Scheidt, W. R. Inorg. Chem. 1984, 23  3192 - 3196

[4] Bjornsson, R.; Lima, F.A.; Weyhermüller, T.; Glatzel, P.; Spatzal, T.; Einsle, O.; Bill, E.; Neese, F.; DeBeer, S.; Chem. Sci. 2014, 5, 3096-3103

[5] K. Weber, T. Krämer, H. Shafaat, T. Weyhermüller, E. Bill, M. van Gastel, F. Neese, W. Lubitz: A functional [NiFe]-hydrogenase model compound that undergoes biologically relevant reversible thiolate protonation. J. Am. Chem. Soc. 2012, 134, 20745-20755