1
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Novotny J, Komorovsky S, Marek R. Paramagnetic Effects in NMR Spectroscopy of Transition-Metal Complexes: Principles and Chemical Concepts. Acc Chem Res 2024; 57:1467-1477. [PMID: 38687879 PMCID: PMC11112740 DOI: 10.1021/acs.accounts.3c00786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 04/14/2024] [Accepted: 04/15/2024] [Indexed: 05/02/2024]
Abstract
ConspectusMagnetic resonance techniques represent a fundamental class of spectroscopic methods used in physics, chemistry, biology, and medicine. Electron paramagnetic resonance (EPR) is an extremely powerful technique for characterizing systems with an open-shell electronic nature, whereas nuclear magnetic resonance (NMR) has traditionally been used to investigate diamagnetic (closed-shell) systems. However, these two techniques are tightly connected by the electron-nucleus hyperfine interaction operating in paramagnetic (open-shell) systems. Hyperfine interaction of the nuclear spin with unpaired electron(s) induces large temperature-dependent shifts of nuclear resonance frequencies that are designated as hyperfine NMR shifts (δHF).Three fundamental physical mechanisms shape the total hyperfine interaction: Fermi-contact, paramagnetic spin-orbit, and spin-dipolar. The corresponding hyperfine NMR contributions can be interpreted in terms of through-bond and through-space effects. In this Account, we provide an elemental theory behind the hyperfine interaction and NMR shifts and describe recent progress in understanding the structural and electronic principles underlying individual hyperfine terms.The Fermi-contact (FC) mechanism reflects the propagation of electron-spin density throughout the molecule and is proportional to the spin density at the nuclear position. As the imbalance in spin density can be thought of as originating at the paramagnetic metal center and being propagated to the observed nucleus via chemical bonds, FC is an excellent indicator of the bond character. The paramagnetic spin-orbit (PSO) mechanism originates in the orbital current density generated by the spin-orbit coupling interaction at the metal center. The PSO mechanism of the ligand NMR shift then reflects the transmission of the spin polarization through bonds, similar to the FC mechanism, but it also makes a substantial through-space contribution in long-range situations. In contrast, the spin-dipolar (SD) mechanism is relatively unimportant at short-range with significant spin polarization on the spectator atom. The PSO and SD mechanisms combine at long-range to form the so-called pseudocontact shift, traditionally used as a structural and dynamics probe in paramagnetic NMR (pNMR). Note that the PSO and SD terms both contribute to the isotropic NMR shift only at the relativistic spin-orbit level of theory.We demonstrate the advantages of calculating and analyzing the NMR shifts at relativistic two- and four-component levels of theory and present analytical tools and approaches based on perturbation theory. We show that paramagnetic NMR effects can be interpreted by spin-delocalization and spin-polarization mechanisms related to chemical bond concepts of electron conjugation in π-space and hyperconjugation in σ-space in the framework of the molecular orbital (MO) theory. Further, we discuss the effects of environment (supramolecular interactions, solvent, and crystal packing) and demonstrate applications of hyperfine shifts in determining the structure of paramagnetic Ru(III) compounds and their supramolecular host-guest complexes with macrocycles.In conclusion, we provide a short overview of possible pNMR applications in the analysis of spectra and electronic structure and perspectives in this field for a general chemical audience.
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Affiliation(s)
- Jan Novotny
- CEITEC
– Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kamenice 5, CZ-625
00 Brno, Czechia
| | - Stanislav Komorovsky
- Institute
of Inorganic Chemistry, Slovak Academy of
Sciences, Dúbravská cesta 9, SK-84536 Bratislava, Slovakia
| | - Radek Marek
- CEITEC
– Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kamenice 5, CZ-625
00 Brno, Czechia
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2
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Islam MA, Pell AJ. Delving into theoretical and computational considerations for accurate calculation of chemical shifts in paramagnetic transition metal systems using quantum chemical methods. Phys Chem Chem Phys 2024; 26:12786-12798. [PMID: 38619872 DOI: 10.1039/d4cp00683f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
The chemical shielding tensor for a paramagnetic system has been derived from the macroscopically observed magnetization using the perturbation theory. An approach to calculate the paramagnetic chemical shifts in transition metal systems based on the spin-only magnetic susceptibility directly evaluated from the ab initio Hilbert space of the electronic Zeeman Hamiltonian has been discussed. Computationally, several advantages are associated with this approach: (a) it includes the state-specific paramagnetic Curie (first-order) and Van Vleck (second-order) contributions of the paramagnetic ion to the paramagnetic chemical shifts; (b) thus it avoids the system-specific modeling and evaluating effectively in terms of the electron paramagnetic resonance (EPR) spin Hamiltonian parameters of the magnetic moment of the paramagnetic ion formulated previously; (c) it can be utilized both in the point-dipole (PD) approximation (in the long-range) and with the quantum chemical (QC) method based the hyperfine tensors (in the short-range). Additionally, we have examined the predictive performance of various density functional theory (DFT) functionals of different families and commonly used core-augmented basis sets for nuclear magnetic resonance (NMR) chemical shifts. A selection of transition metal ion complexes with and without first-order orbital contributions, namely the [M(AcPyOx)3(BPh)]+ complexes of M = Mn2+, Ni2+ and Co2+ ions and CoTp2 complex and their reported NMR chemical shifts are studied from QC methods for illustration.
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Affiliation(s)
- Md Ashraful Islam
- Centre de RMN à Très Hauts Champs de Lyon, UMR-5082, CNRS/UCB Lyon 1/ENS de Lyon, 69100 Villeurbanne, France.
| | - Andrew J Pell
- Centre de RMN à Très Hauts Champs de Lyon, UMR-5082, CNRS/UCB Lyon 1/ENS de Lyon, 69100 Villeurbanne, France.
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3
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Ashuiev A, Allouche F, Islam MA, Carvalho JP, Sanders KJ, Conley MP, Klose D, Lapadula G, Wörle M, Baabe D, Walter MD, Pell AJ, Copéret C, Jeschke G, Pintacuda G, Andersen RA. Geometry and electronic structure of Yb(III)[CH(SiMe 3) 2] 3 from EPR and solid-state NMR augmented by computations. Phys Chem Chem Phys 2024; 26:8734-8747. [PMID: 38416412 PMCID: PMC10936694 DOI: 10.1039/d4cp00281d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 02/12/2024] [Indexed: 02/29/2024]
Abstract
Characterization of paramagnetic compounds, in particular regarding the detailed conformation and electronic structure, remains a challenge, and - still today it often relies solely on the use of X-ray crystallography, thus limiting the access to electronic structure information. This is particularly true for lanthanide elements that are often associated with peculiar structural and electronic features in relation to their partially filled f-shell. Here, we develop a methodology based on the combined use of state-of-the-art magnetic resonance spectroscopies (EPR and solid-state NMR) and computational approaches as well as magnetic susceptibility measurements to determine the electronic structure and geometry of a paramagnetic Yb(III) alkyl complex, Yb(III)[CH(SiMe3)2]3, a prototypical example, which contains notable structural features according to X-ray crystallography. Each of these techniques revealed specific information about the geometry and electronic structure of the complex. Taken together, both EPR and NMR, augmented by quantum chemical calculations, provide a detailed and complementary understanding of such paramagnetic compounds. In particular, the EPR and NMR signatures point to the presence of three-centre-two-electron Yb-γ-Me-β-Si secondary metal-ligand interactions in this otherwise tri-coordinate metal complex, similarly to its diamagnetic Lu analogues. The electronic structure of Yb(III) can be described as a single 4f13 configuration, while an unusually large crystal-field splitting results in a thermally isolated ground Kramers doublet. Furthermore, the computational data indicate that the Yb-carbon bond contains some π-character, reminiscent of the so-called α-H agostic interaction.
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Affiliation(s)
- Anton Ashuiev
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Florian Allouche
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Md Ashraful Islam
- Université de Lyon, Centre de RMN à Très Hauts Champs de Lyon (UMR 5082 - CNRS, ENS Lyon, Université Claude Bernard Lyon 1), F-69100 Villeurbanne, France.
| | - José P Carvalho
- Department of Materials and Environmental Chemistry, Stockholm University, Svänte Arrhenius väg 16 C, 106 91 Stockholm, Sweden
| | - Kevin J Sanders
- Université de Lyon, Centre de RMN à Très Hauts Champs de Lyon (UMR 5082 - CNRS, ENS Lyon, Université Claude Bernard Lyon 1), F-69100 Villeurbanne, France.
| | - Matthew P Conley
- Department of Chemistry and Chemical Sciences, University of California Riverside, 501 Big Springs Road, Riverside, CA 92521, USA
| | - Daniel Klose
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Giuseppe Lapadula
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Michael Wörle
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Dirk Baabe
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Marc D Walter
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Andrew J Pell
- Université de Lyon, Centre de RMN à Très Hauts Champs de Lyon (UMR 5082 - CNRS, ENS Lyon, Université Claude Bernard Lyon 1), F-69100 Villeurbanne, France.
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Gunnar Jeschke
- Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland.
| | - Guido Pintacuda
- Université de Lyon, Centre de RMN à Très Hauts Champs de Lyon (UMR 5082 - CNRS, ENS Lyon, Université Claude Bernard Lyon 1), F-69100 Villeurbanne, France.
| | - Richard A Andersen
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
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4
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Franzke YJ, Bruder F, Gillhuber S, Holzer C, Weigend F. Paramagnetic Nuclear Magnetic Resonance Shifts for Triplet Systems and Beyond with Modern Relativistic Density Functional Methods. J Phys Chem A 2024; 128:670-686. [PMID: 38195394 DOI: 10.1021/acs.jpca.3c07093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
An efficient framework for the calculation of paramagnetic NMR (pNMR) shifts within exact two-component (X2C) theory and (current-dependent) density functional theory (DFT) up to the class of local hybrid functionals (LHFs) is presented. Generally, pNMR shifts for systems with more than one unpaired electron depend on the orbital shielding contribution and a temperature-dependent term. The latter includes zero-field splitting (ZFS), hyperfine coupling (HFC), and the g-tensor. For consistency, we calculate these three tensors at the same level of theory, i.e., using scalar-relativistic X2C augmented with spin-orbit perturbation theory. Results for pNMR chemical shifts of transition-metal complexes reveal that this X2C-DFT framework can yield good results for both the shifts and the individual tensor contributions of metallocenes and related systems, especially if the HFC constant is large. For small HFC constants, the relative error is often large, and sometimes the sign may be off. 4d and 5d complexes with more complicated structures demonstrate the limitations of a fully DFT-based approach. Additionally, a Co-based complex with a very large ZFS and pronounced multireference character is not well described. Here, a hybrid DFT-multireference framework is necessary for accurate results. Our results show that X2C is sufficient to describe relativistic effects and computationally cheaper than a fully relativistic approach. Thus, it allows use of large basis sets for converged HFCs. Overall, current-dependent meta-generalized gradient approximations and LHFs show some potential; however, the currently available functionals leave a lot to be desired, and the predictive power is limited.
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Affiliation(s)
- Yannick J Franzke
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Florian Bruder
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Sebastian Gillhuber
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131 Karlsruhe, Germany
| | - Christof Holzer
- Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology (KIT), Wolfgang-Gaede-Straße 1, 76131 Karlsruhe, Germany
| | - Florian Weigend
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
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5
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Pyykkönen A, Vaara J. Computational NMR of the iron pyrazolylborate complexes [Tp 2Fe] + and Tp 2Fe including solvation and spin-crossover effects. Phys Chem Chem Phys 2023; 25:3121-3135. [PMID: 36621831 DOI: 10.1039/d2cp03721a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Transition metal complexes have important roles in many biological processes as well as applications in fields such as pharmacy, chemistry and materials science. Paramagnetic nuclear magnetic resonance (pNMR) is a valuable tool in understanding such molecules, and theoretical computations are often advantageous or even necessary in the assignment of experimental pNMR signals. We have employed density functional theory (DFT) and the domain-based local pair natural orbital coupled-cluster method with single and double excitations (DLPNO-CCSD), as well as a number of model improvements, to determine the critical hyperfine part of the chemical shifts of the iron pyrazolylborate complexes [Tp2Fe]+ and Tp2Fe using a modern version of the Kurland-McGarvey theory, which is based on parameterising the hyperfine, electronic Zeeman and zero-field splitting interactions via the parameters of the electron paramagnetic resonance Hamiltonian. In the doublet [Tp2Fe]+ system, the calculations suggest a re-assignment of the 13C signal shifts. Consideration of solvent via the conductor-like polarisable continuum model (C-PCM) versus explicit solvent molecules reveals C-PCM alone to be insufficient in capturing the most important solvation effects. Tp2Fe exhibits a spin-crossover effect between a high-spin quintet (S = 2) and a low-spin singlet (S = 0) state, and its recorded temperature dependence can only be reproduced theoretically by accounting for the thermal Boltzmann distribution of the open-shell excited state and the closed-shell ground-state occupations. In these two cases, DLPNO-CCSD is found, in calculating the hyperfine couplings, to be a viable alternative to DFT, the demonstrated shortcomings of which have been a significant issue in the development of computational pNMR.
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Affiliation(s)
- Ari Pyykkönen
- NMR Research Unit, University of Oulu, P.O. Box 3000, Oulu FIN-90014, Finland.
| | - Juha Vaara
- NMR Research Unit, University of Oulu, P.O. Box 3000, Oulu FIN-90014, Finland.
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6
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Andersen ABA, Christiansen RT, Holm-Janas S, Manvell AS, Pedersen KS, Sheptyakov D, Embs JP, Jacobsen H, Dachs E, Vaara J, Lefmann K, Nielsen UG. The magnetic properties of MAl 4(OH) 12SO 4·3H 2O with M = Co 2+, Ni 2+, and Cu 2+ determined by a combined experimental and computational approach. Phys Chem Chem Phys 2023; 25:3309-3322. [PMID: 36630169 DOI: 10.1039/d2cp05362d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The magnetic properties of the nickelalumite-type layered double hydroxides (LDH), MAl4(OH)12(SO4)·3H2O (MAl4-LDH) with M = Co2+ (S = 3/2), Ni2+ (S = 1), or Cu2+ (S = 1/2) were determined by a combined experimental and computational approach. They represent three new inorganic, low-dimensional magnetic systems with a defect-free, structurally ordered magnetic lattice. They exhibit no sign of magnetic ordering down to 2 K in contrast to conventional hydrotalcite LDH. Detailed insight into the complex interplay between the choice of magnetic ion (M2+) and magnetic properties was obtained by a combination of magnetic susceptibility, heat capacity, neutron scattering, solid-state NMR spectroscopy, and first-principles calculations. The NiAl4- and especially CoAl4-LDH have pronounced zero-field splitting (ZFS, easy-axis and easy-plane, respectively) and weak ferromagnetic nearest-neighbour interactions. Thus, they are rare examples of predominantly zero-dimensional spin systems in dense, inorganic matrices. In contrast, CuAl4-LDH (S = 1/2) consists of weakly ferromagnetic S = 1/2 spin chains. For all three MAl4-LDH, good agreement is found between the experimental magnetic parameters (J, D, g) and first-principles quantum chemical calculations, which also predict that the interchain couplings are extremely weak (< 0.1 cm-1). Thus, our approach will be valuable for evaluation and prediction of magnetic properties in other inorganic materials.
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Affiliation(s)
- Anders B A Andersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
| | - Rasmus Tang Christiansen
- Nanoscience Centre, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Sofie Holm-Janas
- Nanoscience Centre, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Anna S Manvell
- Department of Chemistry, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Kasper S Pedersen
- Department of Chemistry, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Denis Sheptyakov
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Jan Peter Embs
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Henrik Jacobsen
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Edgar Dachs
- Department of Chemistry and Physics of Materials, Universität Salzburg, Jakob-Haringerstrasse 2a, A-5020 Salzburg, Austria
| | - Juha Vaara
- NMR Research Unit, University of Oulu, FI-90014 Oulu, Finland
| | - Kim Lefmann
- Nanoscience Centre, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Ulla Gro Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
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7
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Ravera E, Gigli L, Fiorucci L, Luchinat C, Parigi G. The evolution of paramagnetic NMR as a tool in structural biology. Phys Chem Chem Phys 2022; 24:17397-17416. [PMID: 35849063 DOI: 10.1039/d2cp01838a] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Paramagnetic NMR data contain extremely accurate long-range information on metalloprotein structures and, when used in the frame of integrative structural biology approaches, they allow for the retrieval of structural details to a resolution that is not achievable using other techniques. Paramagnetic data thus represent an extremely powerful tool to refine protein models in solution, especially when coupled to X-ray or cryoelectron microscopy data, to monitor the formation of complexes and determine the relative arrangements of their components, and to highlight the presence of conformational heterogeneity. More recently, theoretical and computational advancements in quantum chemical calculations of paramagnetic NMR observables are progressively opening new routes in structural biology, because they allow for the determination of the structure within the coordination sphere of the metal center, thus acting as a loupe on sites that are difficult to observe but very important for protein function.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Lucia Gigli
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Letizia Fiorucci
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
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9
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Jaworski A, Hedin N. Electron correlation and vibrational effects in predictions of paramagnetic NMR shifts. Phys Chem Chem Phys 2022; 24:15230-15244. [PMID: 35703010 DOI: 10.1039/d2cp01206e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electronic structure calculations are fundamentally important for the interpretation of nuclear magnetic resonance (NMR) spectra from paramagnetic systems that include organometallic and inorganic compounds, catalysts, or metal-binding sites in proteins. Prediction of induced paramagnetic NMR shifts requires knowledge of electron paramagnetic resonance (EPR) parameters: the electronic g tensor, zero-field splitting D tensor, and hyperfine A tensor. The isotropic part of A, called the hyperfine coupling constant (HFCC), is one of the most troublesome properties for quantum chemistry calculations. Yet, even relatively small errors in calculations of HFCC tend to propagate into large errors in the predicted NMR shifts. The poor quality of A tensors that are currently calculated using density functional theory (DFT) constitutes a bottleneck in improving the reliability of interpretation of the NMR spectra from paramagnetic systems. In this work, electron correlation effects in calculations of HFCCs with a hierarchy of ab initio methods were assessed, and the applicability of different levels of DFT approximations and the coupled cluster singles and doubles (CCSD) method was tested. These assessments were performed for the set of selected test systems comprising an organic radical, and complexes with transition metal and rare-earth ions, for which experimental data are available. Severe deficiencies of DFT were revealed but the CCSD method was able to deliver good agreement with experimental data for all systems considered, however, at substantial computational costs. We proposed a more computationally tractable alternative, where the A was computed with the coupled cluster theory exploiting locality of electron correlation. This alternative is based on the domain-based local pair natural orbital coupled cluster singles and doubles (DLPNO-CCSD) method. In this way the robustness and reliability of the coupled cluster theory were incorporated into the modern formalism for the prediction of induced paramagnetic NMR shifts, and became applicable to systems of chemical interest. This approach was verified for the bis(cyclopentadienyl)vanadium(II) complex (Cp2V; vanadocene), and the metal-binding site of the Zn2+ → Co2+ substituted superoxide dismutase (SOD) metalloprotein. Excellent agreement with experimental NMR shifts was achieved, which represented a substantial improvement over previous theoretical attempts. The effects of vibrational corrections to orbital shielding and hyperfine tensor were evaluated and discussed within the second-order vibrational perturbation theory (VPT2) framework.
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Affiliation(s)
- Aleksander Jaworski
- Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
| | - Niklas Hedin
- Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
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10
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Khalid I, Khera RA, Ali S, Shahid M. Design, synthesis, and comparative study of optoelectronic properties of arylated triazine-based sulfanilamide derivatives through Suzuki–Miyaura cross-coupling reactions. J Mol Model 2022; 28:44. [DOI: 10.1007/s00894-022-05027-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 01/05/2022] [Indexed: 10/19/2022]
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11
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Molecular designing of tetra-aryl-p-benzoquinones derivatives toward strong optical properties. CHEMICAL PAPERS 2021. [DOI: 10.1007/s11696-021-01834-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Novotný J, Jeremias L, Nimax P, Komorovsky S, Heinmaa I, Marek R. Crystal and Substituent Effects on Paramagnetic NMR Shifts in Transition-Metal Complexes. Inorg Chem 2021; 60:9368-9377. [PMID: 34133172 PMCID: PMC9597657 DOI: 10.1021/acs.inorgchem.1c00204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Nuclear magnetic resonance (NMR)
spectroscopy of paramagnetic molecules
provides detailed information about their molecular and electron-spin
structure. The paramagnetic NMR spectrum is a very rich source of
information about the hyperfine interaction between the atomic nuclei
and the unpaired electron density. The Fermi-contact contribution
to ligand hyperfine NMR shifts is particularly informative about the
nature of the metal–ligand bonding and the structural arrangements
of the ligands coordinated to the metal center. In this account, we
provide a detailed experimental and theoretical NMR study of compounds
of Cr(III) and Cu(II) coordinated with substituted acetylacetonate
(acac) ligands in the solid state. For the first time, we report the
experimental observation of extremely paramagnetically deshielded 13C NMR resonances for these compounds in the range of 900–1200
ppm. We demonstrate an excellent agreement between the experimental
NMR shifts and those calculated using relativistic density-functional
theory. Crystal packing is shown to significantly influence the NMR
shifts in the solid state, as demonstrated by theoretical calculations
of various supramolecular clusters. The resonances are assigned to
individual atoms in octahedral Cr(acac)3 and square-planar
Cu(acac)2 compounds and interpreted by different electron
configurations and magnetizations at the central metal atoms resulting
in different spin delocalizations and polarizations of the ligand
atoms. Further, effects of substituents on the 13C NMR
resonance of the ipso carbon atom reaching almost 700 ppm for Cr(acac)3 compounds are interpreted based on the analysis of Fermi-contact
hyperfine contributions. The
ligand NMR shifts in paramagnetic acetylacetonato Cr(III)
and Cu(II) complexes have been predicted and measured in the solid
state and interpreted by relativistic DFT calculations. The effects
of the metal atom, ligand, and crystal packing on the spin delocalization
and polarization reflected in the Fermi-contact contribution to the
hyperfine interaction are rationalized.
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Affiliation(s)
- Jan Novotný
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84536 Bratislava, Slovakia
| | - Lukáš Jeremias
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,Department of Chemistry and Biochemistry, Faculty of AgriSciences, Mendel University, Zemědělská 1, CZ-613 00 Brno, Czechia
| | - Patrick Nimax
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia
| | - Stanislav Komorovsky
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84536 Bratislava, Slovakia
| | - Ivo Heinmaa
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, EE-12618 Tallinn, Estonia
| | - Radek Marek
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia.,National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czechia
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13
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Ma Z, Lu C, Chen J, Rokicińska A, Kuśtrowski P, Coridan R, Dronskowski R, Slabon A, Jaworski A. CeTiO 2N oxynitride perovskite: paramagnetic 14N MAS NMR without paramagnetic shifts. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2021. [DOI: 10.1515/znb-2021-0031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
14N magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectra of diamagnetic LaTiO2N perovskite oxynitride and its paramagnetic counterpart CeTiO2N are presented. The latter, to the best of our knowledge, constitutes the first high-resolution 14N MAS NMR spectrum collected from a paramagnetic solid material. The unpaired 4f-electrons in CeTiO2N do not induce a paramagnetic 14N NMR shift. This is remarkable given the direct Ce−N contacts in the structure for which ab initio calculations predict substantial Ce→14N contact shift interaction. The same effect is revealed with 14N MAS NMR for SrWO2N (unpaired 5d-electrons).
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Affiliation(s)
- Zili Ma
- Chair of Solid-State and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University , Landoltweg 1, D-52056 Aachen , Germany
| | - Can Lu
- Chair of Solid-State and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University , Landoltweg 1, D-52056 Aachen , Germany
| | - Jianhong Chen
- Department of Materials and Environmental Chemistry , Stockholm University , SE-106 91 , Stockholm , Sweden
| | - Anna Rokicińska
- Faculty of Chemistry, Jagiellonian University , Gronostajowa 2, 30-387 Kraków , Poland
| | - Piotr Kuśtrowski
- Faculty of Chemistry, Jagiellonian University , Gronostajowa 2, 30-387 Kraków , Poland
| | - Robert Coridan
- Department of Chemistry and Biochemistry , University of Arkansas , Fayetteville , AR 72701 , USA
| | - Richard Dronskowski
- Chair of Solid-State and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University , Landoltweg 1, D-52056 Aachen , Germany
| | - Adam Slabon
- Department of Materials and Environmental Chemistry , Stockholm University , SE-106 91 , Stockholm , Sweden
| | - Aleksander Jaworski
- Department of Materials and Environmental Chemistry , Stockholm University , SE-106 91 , Stockholm , Sweden
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14
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Pell AJ. A method to calculate the NMR spectra of paramagnetic species using thermalized electronic relaxation. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 326:106939. [PMID: 33744830 DOI: 10.1016/j.jmr.2021.106939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/06/2021] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
For paramagnetic species, it has been long understood that the hyperfine interaction between the unpaired electrons and the nucleus results in a nuclear magnetic resonance (NMR) peak that is shifted by a paramagnetic shift, rather than split by the coupling, due to an averaging of the electronic magnetic moment caused by electronic relaxation that is fast in comparison to the hyperfine coupling constant. However, although this feature of paramagnetic NMR has formed the basis of all theories of the paramagnetic shift, the precise theory and mechanism of the electronic relaxation required to predict this result has never been discussed, nor has the assertion been tested. In this paper, we show that the standard semi-classical Redfield theory of relaxation fails to predict a paramagnetic shift, as does any attempt to correct for the semi-classical theory using modifications such as the inhomogeneous master equation or Levitt-di Bari thermalization. In fact, only the recently-introduced Lindbladian theory of relaxation in magnetic resonance [J.Magn.Reson., 310, 106645 (2019)] is able to correctly predict the paramagnetic shift tensor and relaxation-induced linewidth in pNMR. Furthermore, this new formalism is able to predict the NMR spectra of paramagnetic species outside the high-temperature and weak-order limits, and is therefore also applicable to dynamic nuclear polarization. The formalism is tested by simulations of five case studies, which include Fermi-contact and spin-dipolar hyperfine couplings, g-anisotropy, zero-field splitting, high and low temperatures, and fast and slow electronic relaxation.
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Affiliation(s)
- Andrew J Pell
- Department of Materials and Environmental Chemistry, Stockholm University, Svänte Arrhenius väg 16 C, 106 91 Stockholm, Sweden; Centre de RMN Trés Hauts Champs de Lyon (UMR5082 CNRS/ENS-Lyon/Université Claude Bernard Lyon 1), Université de Lyon, 5 rue de la Doua, 69100 Villeurbanne, France.
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15
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Autillo M, Islam MA, Héron J, Guérin L, Acher E, Tamain C, Illy MC, Moisy P, Colineau E, Griveau JC, Berthon C, Bolvin H. Temperature Dependence of 1 H Paramagnetic Chemical Shifts in Actinide Complexes, Beyond Bleaney's Theory: The An VI O 2 2+ -Dipicolinic Acid Complexes (An=Np, Pu) as an Example. Chemistry 2021; 27:7138-7153. [PMID: 33406305 DOI: 10.1002/chem.202005147] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/24/2020] [Indexed: 01/02/2023]
Abstract
Actinide +VI complexes ( A n V I = U V I , N p V I and P u V I ) with dipicolinic acid derivatives were synthesized and characterized by powder XRD, SQUID magnetometry and NMR spectroscopy. In addition, N p V I and P u V I complexes were described by first principles CAS based and two-component spin-restricted DFT methods. The analysis of the 1 H paramagnetic NMR chemical shifts for all protons of the ligands according to the X-rays structures shows that the Fermi contact contribution is negligible in agreement with spin density determined by unrestricted DFT. The magnetic susceptibility tensor is determined by combining SQUID, pNMR shifts and Evans' method. The SO-RASPT2 results fit well the experimental magnetic susceptibility and pNMR chemical shifts. The role of the counterions in the solid phase is pointed out; their presence impacts the magnetic properties of the N p V I complex. The temperature dependence of the pNMR chemical shifts has a strong 1 / T contribution, contrarily to Bleaney's theory for lanthanide complexes. The fitting of the temperature dependence of the pNMR chemical shifts and SQUID magnetic susceptibility by a two-Kramers-doublet model for the N p V I complex and a non-Kramers-doublet model for the P u V I complex allows for the experimental evaluation of energy gaps and magnetic moments of the paramagnetic center.
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Affiliation(s)
- Matthieu Autillo
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France
| | - Md Ashraful Islam
- Laboratoire de Chimie et Physique Quantiques, CNRS, Université Toulouse III, 118 route de Narbonne, 31062, Toulouse, France
| | - Julie Héron
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315, Oslo, Norway
| | - Laetitia Guérin
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France
| | - Eleonor Acher
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France
| | - Christelle Tamain
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France
| | - Marie-Claire Illy
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France.,Planitec, CEA Marcoule, 30207, Bagnols/Cèze, France
| | - Philippe Moisy
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France
| | - Eric Colineau
- European Commission Joint Research Centre (JRC), 76125, Karlsruhe, Germany
| | | | - Claude Berthon
- CEA, DES, ISEC, DMRC, Univ Montpellier, 30207, Bagnols sur Cèze, France
| | - Hélène Bolvin
- Laboratoire de Chimie et Physique Quantiques, CNRS, Université Toulouse III, 118 route de Narbonne, 31062, Toulouse, France
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16
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Sequence-specific assignments in NMR spectra of paramagnetic systems: A non-systematic approach. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2020.119984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Blahut J, Benda L, Kotek J, Pintacuda G, Hermann P. Paramagnetic Cobalt(II) Complexes with Cyclam Derivatives: Toward 19F MRI Contrast Agents. Inorg Chem 2020; 59:10071-10082. [DOI: 10.1021/acs.inorgchem.0c01216] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jan Blahut
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12843 Prague 2, Czech Republic
- High-Field NMR Centre, CNRS FRE2034/UCB de Lyon 1/ENS de Lyon, 5 rue de la Doua, 69100 Lyon-Villeurbanne, France
| | - Ladislav Benda
- High-Field NMR Centre, CNRS FRE2034/UCB de Lyon 1/ENS de Lyon, 5 rue de la Doua, 69100 Lyon-Villeurbanne, France
| | - Jan Kotek
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12843 Prague 2, Czech Republic
| | - Guido Pintacuda
- High-Field NMR Centre, CNRS FRE2034/UCB de Lyon 1/ENS de Lyon, 5 rue de la Doua, 69100 Lyon-Villeurbanne, France
| | - Petr Hermann
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12843 Prague 2, Czech Republic
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18
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Pyykkönen A, Feher R, Köhler FH, Vaara J. Paramagnetic Pyrazolylborate Complexes Tp 2M and Tp* 2M: 1H, 13C, 11B, and 14N NMR Spectra and First-Principles Studies of Chemical Shifts. Inorg Chem 2020; 59:9294-9307. [PMID: 32558559 DOI: 10.1021/acs.inorgchem.0c01176] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The paramagnetic pyrazolylborates Tp2M and Tp*2M (M = Cu, Ni, Co, Fe, Mn, Cr, V) as well as [Tp2M]+ and [Tp*2M]+ (M = Fe, Cr, V) have been synthesized and their NMR spectra recorded. The 1H signal shift ranges vary from ∼30 ppm (Cu(II) and V(III)) to ∼220 ppm (Co(II)), and the 13C signal shift ranges from ∼180 ppm (Fe(III)) to ∼1150 ppm (Cr(II)). The 11B and 14N shifts are ∼360 and ∼730 ppm, respectively. Both negative and positive shifts have been observed for all nuclei. The narrow NMR signals of the Co(II), Fe(II), Fe(III), and V(III) derivatives provide resolved 13C,1H couplings. All chemical shifts have been calculated from first-principles on a modern version of Kurland-McGarvey theory which includes optimized structures, zero-field splitting, and g tensors, as well as signal shift contributions. Temperature dependence in the Fe(II) spin-crossover complex results from the equilibrium of the ground singlet and the excited quintet. We illustrate both the assignment and analysis capabilities, as well as the shortcomings of the current computational methodology.
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Affiliation(s)
- Ari Pyykkönen
- NMR Research Unit, University of Oulu, P.O. Box 3000, Oulu FI-90014, Finland
| | - Robert Feher
- Department Chemie, Technische Universität München, D-85748 Garching, Germany
| | - Frank H Köhler
- Department Chemie, Technische Universität München, D-85748 Garching, Germany
| | - Juha Vaara
- NMR Research Unit, University of Oulu, P.O. Box 3000, Oulu FI-90014, Finland
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19
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Andersen ABA, Pyykkönen A, Jensen HJA, McKee V, Vaara J, Nielsen UG. Remarkable reversal of 13C-NMR assignment in d 1, d 2 compared to d 8, d 9 acetylacetonate complexes: analysis and explanation based on solid-state MAS NMR and computations. Phys Chem Chem Phys 2020; 22:8048-8059. [PMID: 32239061 DOI: 10.1039/d0cp00980f] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
13C solid-state MAS NMR spectra of a series of paramagnetic metal acetylacetonate complexes; [VO(acac)2] (d1, S = ½), [V(acac)3] (d2, S = 1), [Ni(acac)2(H2O)2] (d8, S = 1), and [Cu(acac)2] (d9, S = ½), were assigned using modern NMR shielding calculations. This provided a reliable assignment of the chemical shifts and a qualitative insight into the hyperfine couplings. Our results show a reversal of the isotropic 13C shifts, δiso(13C), for CH3 and CO between the d1 and d2versus the d8 and d9 acetylacetonate complexes. The CH3 shifts change from about -150 ppm (d1,2) to roughly 1000 ppm (d8,9), whereas the CO shifts decrease from 800 ppm to about 150 ppm for d1,2 and d8,9, respectively. This was rationalized by comparison of total spin-density plots and computed contact couplings to those corresponding to singly occupied molecular orbitals (SOMOs). This revealed the interplay between spin delocalization of the SOMOs and spin polarization of the lower-energy MOs, influenced by both the molecular symmetry and the d-electron configuration. A large positive chemical shift results from spin delocalization and spin polarization acting in the same direction, whereas their cancellation corresponds to a small shift. The SOMO(s) for the d8 and d9 complexes are σ-like, implying spin-delocalization on the CH3 and CO groups of the acac ligand, cancelled only for CO by spin polarization. In contrast, the SOMOs of the d1 and d2 systems are π-like and a large CO-shift results from spin polarization, which accounts for the reversed assignment of δiso(13C) for CH3 and CO.
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Affiliation(s)
- Anders B A Andersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
| | - Ari Pyykkönen
- NMR Research Unit, University of Oulu, FI-90014, Finland
| | - Hans Jørgen Aa Jensen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
| | - Vickie McKee
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark. and School of Chemical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Juha Vaara
- NMR Research Unit, University of Oulu, FI-90014, Finland
| | - Ulla Gro Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
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20
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Quantitative prediction of electronic absorption spectra of copper(II)-bioligand systems: Validation and applications. J Inorg Biochem 2019; 204:110953. [PMID: 31816442 DOI: 10.1016/j.jinorgbio.2019.110953] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 02/06/2023]
Abstract
The visible region of the electronic absorption spectra of Cu(II) complexes was studied by time-dependent density functional theory (TD-DFT). The performance of twelve functionals in the prediction of absorption maxima (λmax) was tested on eleven compounds with different geometry, donors and charge. The ranking of the functionals for λmax was determined in terms of mean absolute percent deviation (MAPD) and standard deviation (SD) and it is as follows: BHandHLYP > M06 ≫ CAM-B3LYP ≫ MPW1PW91 ~ B1LYP ~ BLYP > HSE06 ~ B3LYP > B3P86 ~ ω-B97x-D ≫ TPSSh ≫ M06-2X (MAPD) and BHandHLYP > M06 ~ HSE06 > ω-B97x-D ~ CAM-B3LYP ~ MPW1PW91 > B1LYP ~ B3LYP > B3P86 > BLYP ≫ TPSSh ≫ M06-2X (SD). With BHandHLYP functional the MAPD is 3.1% and SD is 2.3%, while with M06 the MAPD is 3.7% and SD is 3.7%. The protocol validated in the first step of the study was applied to: i) calculate the number of transitions in the spectra and relate them to the geometry of Cu(II) species; ii) determine the coordination of axial water(s); iii) predict the electronic spectra of the systems where Cu(II) is bound to human serum albumin (HSA) and to the regions 94-97 and 108-112 of prion protein (PrP). The results indicate that the proposed computational protocol allows a successful prediction of the electronic spectra of Cu(II) species and to relate an experimental spectrum to a specific structure.
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21
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Parigi G, Ravera E, Luchinat C. Magnetic susceptibility and paramagnetism-based NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:211-236. [PMID: 31779881 DOI: 10.1016/j.pnmrs.2019.06.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 05/18/2023]
Abstract
The magnetic interactions between the nuclear magnetic moment and the magnetic moment of unpaired electron(s) depend on the structure and dynamics of the molecules where the paramagnetic center is located and of their partners. The long-range nature of the magnetic interactions is thus a reporter of invaluable information for structural biology studies, when other techniques often do not provide enough data for the atomic-level characterization of the system. This precious information explains the flourishing of paramagnetism-assisted NMR studies in recent years. Many paramagnetic effects are related to the magnetic susceptibility of the paramagnetic metal. Although these effects have been known for more than half a century, different theoretical models and new approaches have been proposed in the last decade. In this review, we have summarized the consequences for NMR spectroscopy of magnetic interactions between nuclear and electron magnetic moments, and thus of the presence of a magnetic susceptibility due to metals, and we do so using a unified notation.
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Affiliation(s)
- Giacomo Parigi
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Enrico Ravera
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
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22
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Mondal A, Kaupp M. Quantum-chemical study of 7Li NMR shifts in the context of delithiation of paramagnetic lithium vanadium phosphate, Li 3V 2(PO 4) 3 (LVP). SOLID STATE NUCLEAR MAGNETIC RESONANCE 2019; 101:89-100. [PMID: 31132716 DOI: 10.1016/j.ssnmr.2019.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
The lithium NMR shifts of three paramagnetic materials important in the charging/discharging processes of lithium vanadium phosphate cathode materials have been studied by large-scale quantum-chemical methodology. Namely, the 7Li NMR shifts of the fully lithiated Li3V2(PO4)3 (LVP3.0), and of the partly delithiated Li2.5V2(PO4)3 (LVP2.5) and Li2V2(PO4)3 (LVP2.0), have been computed and analyzed using a recently proposed approach (A. Mondal, M. Kaupp J. Phys. Chem. C 123 (2019) 8387-8405) that accounts for the Fermi-contact, pseudo-contact, as well as orbital shifts, combining periodic computations with an incremental cluster model. LVP3.0 and LVP2.0 exhibit three and two unique Li sites, respectively, which could be assigned to their experimental 7Li NMR signals. In case of LVP2.0, the computations clearly assigned the signals at 143 ppm and 77 ppm to the Li(1) and Li(2) sites, respectively, even though the latter is connected to Vb(+III d2 sites and the former to Va(+IV) d1 sites. LVP2.5 is the most complex of these three materials, exhibiting a 50% occupation of Li(3) sites, which generates much more complicated Li NMR spectra with seven peaks that partly are closely spaced. Exploring three different occupation patterns, the computations can clearly assign five of the seven signals to one type of Li site and give most probable assignments for the two remaining signals. Notably, the calculations support seven signals to be assigned to LVP2.5, while previous interpretations took two of the signals as being entirely due to contamination by LVP2.0. The accuracy of the computations could probably be improved further by full DFT optimization of large super-cell structures. This work suggests that first-principles computations of NMR shifts of extended paramagnetic solids provide an important tool for the analysis of even rather complex NMR spectra.
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Affiliation(s)
- Arobendo Mondal
- Institut für Chemie, Theoretische Chemie, Technische Universität Berlin, Sekr. C7, Strasse des 17. Juni 135, D-10623, Berlin, Germany
| | - Martin Kaupp
- Institut für Chemie, Theoretische Chemie, Technische Universität Berlin, Sekr. C7, Strasse des 17. Juni 135, D-10623, Berlin, Germany.
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23
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Parigi G, Benda L, Ravera E, Romanelli M, Luchinat C. Pseudocontact shifts and paramagnetic susceptibility in semiempirical and quantum chemistry theories. J Chem Phys 2019; 150:144101. [PMID: 30981251 DOI: 10.1063/1.5037428] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Pseudocontact shifts are traditionally described as a function of the anisotropy of the paramagnetic susceptibility tensor, according to the semiempirical theory mainly developed by Kurland and McGarvey [J. Magn. Reson. 2, 286-301 (1970)]. The paramagnetic susceptibility tensor is required to be symmetric. Applying point-dipole approximation to the quantum chemistry theory of hyperfine shift, pseudocontact shifts are found to scale with a non-symmetric tensor that differs by a factor gT/ge from the paramagnetic susceptibility tensor derived within the semiempirical framework. We analyze the foundations of the Kurland-McGarvey pseudocontact shift expression and recall that it is inherently based on the Russell-Saunders (LS) coupling approximation for the spin-orbit coupling. We show that the difference between the semiempirical and quantum chemistry pseudocontact shift expressions arises directly from the different treatment of the orbital contribution to the hyperfine coupling.
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Affiliation(s)
- Giacomo Parigi
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Ladislav Benda
- Centre de RMN à Très Hauts Champs, FRE 2034 CNRS, ENS de Lyon, UCB Lyon 1, 5 Rue de la Doua, 69100 Villeurbanne (Lyon), France
| | - Enrico Ravera
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Maurizio Romanelli
- Department of Earth Sciences, University of Florence, Via Giorgio La Pira 4, 50121 Florence, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
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24
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Pell AJ, Pintacuda G, Grey CP. Paramagnetic NMR in solution and the solid state. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 111:1-271. [PMID: 31146806 DOI: 10.1016/j.pnmrs.2018.05.001] [Citation(s) in RCA: 210] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 05/11/2018] [Accepted: 05/12/2018] [Indexed: 05/22/2023]
Abstract
The field of paramagnetic NMR has expanded considerably in recent years. This review addresses both the theoretical description of paramagnetic NMR, and the way in which it is currently practised. We provide a review of the theory of the NMR parameters of systems in both solution and the solid state. Here we unify the different languages used by the NMR, EPR, quantum chemistry/DFT, and magnetism communities to provide a comprehensive and coherent theoretical description. We cover the theory of the paramagnetic shift and shift anisotropy in solution both in the traditional formalism in terms of the magnetic susceptibility tensor, and using a more modern formalism employing the relevant EPR parameters, such as are used in first-principles calculations. In addition we examine the theory first in the simple non-relativistic picture, and then in the presence of spin-orbit coupling. These ideas are then extended to a description of the paramagnetic shift in periodic solids, where it is necessary to include the bulk magnetic properties, such as magnetic ordering at low temperatures. The description of the paramagnetic shift is completed by describing the current understanding of such shifts due to lanthanide and actinide ions. We then examine the paramagnetic relaxation enhancement, using a simple model employing a phenomenological picture of the electronic relaxation, and again using a more complex state-of-the-art theory which incorporates electronic relaxation explicitly. An additional important consideration in the solid state is the impact of bulk magnetic susceptibility effects on the form of the spectrum, where we include some ideas from the field of classical electrodynamics. We then continue by describing in detail the solution and solid-state NMR methods that have been deployed in the study of paramagnetic systems in chemistry, biology, and the materials sciences. Finally we describe a number of case studies in paramagnetic NMR that have been specifically chosen to highlight how the theory in part one, and the methods in part two, can be used in practice. The systems chosen include small organometallic complexes in solution, solid battery electrode materials, metalloproteins in both solution and the solid state, systems containing lanthanide ions, and multi-component materials used in pharmaceutical controlled-release formulations that have been doped with paramagnetic species to measure the component domain sizes.
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Affiliation(s)
- Andrew J Pell
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Svante Arrhenius väg 16 C, SE-106 91 Stockholm, Sweden.
| | - Guido Pintacuda
- Institut des Sciences Analytiques (CNRS UMR 5280, ENS de Lyon, UCB Lyon 1), Université de Lyon, 5 rue de la Doua, 69100 Villeurbanne, France
| | - Clare P Grey
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
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25
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Bora PL, Novotný J, Ruud K, Komorovsky S, Marek R. Electron-Spin Structure and Metal–Ligand Bonding in Open-Shell Systems from Relativistic EPR and NMR: A Case Study of Square-Planar Iridium Catalysts. J Chem Theory Comput 2018; 15:201-214. [DOI: 10.1021/acs.jctc.8b00914] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pankaj L. Bora
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5/A4, CZ-62500 Brno, Czechia
| | - Jan Novotný
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5/A4, CZ-62500 Brno, Czechia
| | - Kenneth Ruud
- Hylleraas Centre for Quantum Molecular Science, Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway
| | - Stanislav Komorovsky
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84536 Bratislava, Slovakia
| | - Radek Marek
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5/A4, CZ-62500 Brno, Czechia
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26
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Mareš J, Vaara J. Ab initio paramagnetic NMR shifts via point-dipole approximation in a large magnetic-anisotropy Co(ii) complex. Phys Chem Chem Phys 2018; 20:22547-22555. [PMID: 30141806 DOI: 10.1039/c8cp04123g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Transition metal complexes can possess a large magnetic susceptibility anisotropy, facilitating applications such as paramagnetic tags or shift agents in nuclear magnetic resonance (NMR) spectroscopy. Due to its g-shift and zero-field splitting (ZFS) we demonstrate on a Co(ii) clathrochelate with an aliphatic 16-carbon chain, a modern approach for ab initio calculation of paramagnetic susceptibility. Due to its large anisotropy, large linear dimension but relatively low number of atoms, the chosen complex is especially well-suited for testing the long-range point-dipole approximation (PDA) for the pseudocontact shifts (PCSs) of paramagnetic NMR. A static structure of the complex is used to compare the limiting long-distance PDA with full first-principles quantum-mechanical calculation. A non-symmetric formula for the magnetic susceptibility tensor is necessary to be consistent with the latter. Comparison with experimental shifts is performed by conformational averaging over the chain dynamics using Monte Carlo simulation. We observe satisfactory accuracy from the rudimentary simulation and, more importantly, demonstrate the fast applicability of the ab initio PDA.
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Affiliation(s)
- Jiří Mareš
- NMR Research Unit, University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland.
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27
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Jeremias L, Novotný J, Repisky M, Komorovsky S, Marek R. Interplay of Through-Bond Hyperfine and Substituent Effects on the NMR Chemical Shifts in Ru(III) Complexes. Inorg Chem 2018; 57:8748-8759. [PMID: 30004686 DOI: 10.1021/acs.inorgchem.8b00073] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The links between the molecular structure and nuclear magnetic resonance (NMR) parameters of paramagnetic transition-metal complexes are still relatively unexplored. This applies particularly to the contact term of the hyperfine contribution to the NMR chemical shift. We report combining experimental NMR with relativistic density functional theory (DFT) to study a series of Ru(III) complexes with 2-substituted β-diketones. A series of complexes with systematically varied substituents was synthesized and analyzed using 1H and 13C NMR spectroscopy. The NMR spectra recorded at several temperatures were used to construct Curie plots and estimate the temperature-independent (orbital) and temperature-dependent (hyperfine) contributions to the NMR shift. Relativistic DFT calculations of electron paramagnetic resonance and NMR parameters were performed to interpret the experimental observations. The effects of individual factors such as basis set, density functional, exact-exchange admixture, and relativity are analyzed and discussed. Based on the calibration study in this work, the fully relativistic Dirac-Kohn-Sham (DKS) method, the GIAO approach (orbital shift), the PBE0 functional with the triple-ζ valence basis sets, and the polarizable continuum model for describing solvent effects were selected to calculate the NMR parameters. The hyperfine contribution to the total paramagnetic NMR (pNMR) chemical shift is shown to be governed by the Fermi-contact (FC) term, and the substituent effect (H vs Br) on the through-bond FC shifts is analyzed, interpreted, and discussed in terms of spin-density distribution, atomic spin populations, and molecular-orbital theory. In contrast to the closed-shell systems of Rh(III), the presence of a single unpaired electron in the open-shell Ru(III) analogs significantly alters the NMR resonances of the ligand atoms distant from the metal center in synergy with the substituent effect.
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Affiliation(s)
- Lukáš Jeremias
- CEITEC-Central European Institute of Technology , Masaryk University , Kamenice 5/A4 , CZ-625 00 Brno , Czechia
| | - Jan Novotný
- CEITEC-Central European Institute of Technology , Masaryk University , Kamenice 5/A4 , CZ-625 00 Brno , Czechia
| | - Michal Repisky
- Hylleraas Centre for Quantum Molecular Science, Department of Chemistry , UiT-The Arctic University of Norway , N-9037 Tromsø , Norway
| | - Stanislav Komorovsky
- Institute of Inorganic Chemistry , Slovak Academy of Sciences , Dúbravská cesta 9 , SK-84536 Bratislava , Slovakia
| | - Radek Marek
- CEITEC-Central European Institute of Technology , Masaryk University , Kamenice 5/A4 , CZ-625 00 Brno , Czechia
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28
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Wittmann T, Mondal A, Tschense CBL, Wittmann JJ, Klimm O, Siegel R, Corzilius B, Weber B, Kaupp M, Senker J. Probing Interactions of N-Donor Molecules with Open Metal Sites within Paramagnetic Cr-MIL-101: A Solid-State NMR Spectroscopic and Density Functional Theory Study. J Am Chem Soc 2018; 140:2135-2144. [DOI: 10.1021/jacs.7b10148] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Thomas Wittmann
- Inorganic
Chemistry III, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Arobendo Mondal
- Institute
of Chemistry, Theoretical Chemistry/Quantum Chemistry, Technical University of Berlin, Sekr. C7, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Carsten B. L. Tschense
- Inorganic
Chemistry III, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Johannes J. Wittmann
- Institute
of Physical and Theoretical Chemistry and Institute of Biophysical
Chemistry, Goethe University Frankfurt, Max-von-Laue-Straße 7-9, 60438 Frankfurt am Main, Germany
| | - Ottokar Klimm
- Inorganic
Chemistry II, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Renée Siegel
- Inorganic
Chemistry III, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Björn Corzilius
- Institute
of Physical and Theoretical Chemistry and Institute of Biophysical
Chemistry, Goethe University Frankfurt, Max-von-Laue-Straße 7-9, 60438 Frankfurt am Main, Germany
| | - Birgit Weber
- Inorganic
Chemistry II, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Martin Kaupp
- Institute
of Chemistry, Theoretical Chemistry/Quantum Chemistry, Technical University of Berlin, Sekr. C7, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Juergen Senker
- Inorganic
Chemistry III, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
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29
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Mondal A, Gaultois MW, Pell AJ, Iannuzzi M, Grey CP, Hutter J, Kaupp M. Large-Scale Computation of Nuclear Magnetic Resonance Shifts for Paramagnetic Solids Using CP2K. J Chem Theory Comput 2017; 14:377-394. [DOI: 10.1021/acs.jctc.7b00991] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Arobendo Mondal
- Institut
für Chemie, Theoretische Chemie/Quantenchemie, Technische Universität Berlin, Sekretariat C7, Strasse des 17 Juni 135, D-10623 Berlin, Germany
| | - Michael W. Gaultois
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Andrew J. Pell
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden
| | - Marcella Iannuzzi
- Institut
für Chemie, Universität Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Clare P. Grey
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Jürg Hutter
- Institut
für Chemie, Universität Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Martin Kaupp
- Institut
für Chemie, Theoretische Chemie/Quantenchemie, Technische Universität Berlin, Sekretariat C7, Strasse des 17 Juni 135, D-10623 Berlin, Germany
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30
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A comparative study of DFT calculated and experimental UV/Visible spectra for thirty carboline and carbazole based compounds. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.07.093] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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31
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Rouf SA, Jakobsen VB, Mareš J, Jensen ND, McKenzie CJ, Vaara J, Nielsen UG. Assignment of solid-state 13C and 1H NMR spectra of paramagnetic Ni(II) acetylacetonate complexes aided by first-principles computations. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2017; 87:29-37. [PMID: 28759801 DOI: 10.1016/j.ssnmr.2017.07.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 07/07/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
Recent advances in computational methodology allowed for first-principles calculations of the nuclear shielding tensor for a series of paramagnetic nickel(II) acetylacetonate complexes, [Ni(acac)2L2] with L = H2O, D2O, NH3, ND3, and PMe2Ph have provided detailed insight into the origin of the paramagnetic contributions to the total shift tensor. This was employed for the assignment of the solid-state 1,2H and 13C MAS NMR spectra of these compounds. The two major contributions to the isotropic shifts are by orbital (diamagnetic-like) and contact mechanism. The orbital shielding, contact, as well as dipolar terms all contribute to the anisotropic component. The calculations suggest reassignment of the 13C methyl and carbonyl resonances in the acac ligand [Inorg. Chem.53, 2014, 399] leading to isotropic paramagnetic shifts of δ(13C) ≈ 800-1100 ppm and ≈180-300 ppm for 13C for the methyl and carbonyl carbons located three and two bonds away from the paramagnetic Ni(II) ion, respectively. Assignment using three different empirical correlations, i.e., paramagnetic shifts, shift anisotropy, and relaxation (T1) were ambiguous, however the latter two support the computational results. Thus, solid-state NMR spectroscopy in combination with modern quantum-chemical calculations of paramagnetic shifts constitutes a promising tool for structural investigations of metal complexes and materials.
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Affiliation(s)
- Syed Awais Rouf
- NMR Research Unit, University of Oulu, P.O. BOX 3000, FIN-90014 Oulu, Finland
| | - Vibe Boel Jakobsen
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark; School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland
| | - Jiří Mareš
- NMR Research Unit, University of Oulu, P.O. BOX 3000, FIN-90014 Oulu, Finland
| | - Nicholai Daugaard Jensen
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Christine J McKenzie
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Juha Vaara
- NMR Research Unit, University of Oulu, P.O. BOX 3000, FIN-90014 Oulu, Finland
| | - Ulla Gro Nielsen
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark.
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32
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Benchmark study of bond dissociation energy of Si X (X F, Cl, Br, N, O, H and C) bond using density functional theory (DFT). J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.04.066] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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33
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Ravera E, Parigi G, Luchinat C. Perspectives on paramagnetic NMR from a life sciences infrastructure. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 282:154-169. [PMID: 28844254 DOI: 10.1016/j.jmr.2017.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/28/2017] [Accepted: 07/31/2017] [Indexed: 05/17/2023]
Abstract
The effects arising in NMR spectroscopy because of the presence of unpaired electrons, collectively referred to as "paramagnetic NMR" have attracted increasing attention over the last decades. From the standpoint of the structural and mechanistic biology, paramagnetic NMR provides long range restraints that can be used to assess the accuracy of crystal structures in solution and to improve them by simultaneous refinements through NMR and X-ray data. These restraints also provide information on structure rearrangements and conformational variability in biomolecular systems. Theoretical improvements in quantum chemistry calculations can nowadays allow for accurate calculations of the paramagnetic data from a molecular structural model, thus providing a tool to refine the metal coordination environment by matching the paramagnetic effects observed far away from the metal. Furthermore, the availability of an improved technology (higher fields and faster magic angle spinning) has promoted paramagnetic NMR applications in the fast-growing area of biomolecular solid-state NMR. Major improvements in dynamic nuclear polarization have been recently achieved, especially through the exploitation of the Overhauser effect occurring through the contact-driven relaxation mechanism: the very large enhancement of the 13C signal observed in a variety of liquid organic compounds at high fields is expected to open up new perspectives for applications of solution NMR.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy.
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34
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Rouf SA, Mareš J, Vaara J. Relativistic Approximations to Paramagnetic NMR Chemical Shift and Shielding Anisotropy in Transition Metal Systems. J Chem Theory Comput 2017. [DOI: 10.1021/acs.jctc.7b00168] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Syed Awais Rouf
- NMR Research Unit, University of Oulu, P.O.
Box 3000, Oulu FIN-90014, Finland
| | - Jiří Mareš
- NMR Research Unit, University of Oulu, P.O.
Box 3000, Oulu FIN-90014, Finland
| | - Juha Vaara
- NMR Research Unit, University of Oulu, P.O.
Box 3000, Oulu FIN-90014, Finland
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35
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Cherry PJ, Rouf SA, Vaara J. Paramagnetic Enhancement of Nuclear Spin–Spin Coupling. J Chem Theory Comput 2017; 13:1275-1283. [DOI: 10.1021/acs.jctc.6b01080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Peter John Cherry
- Institute of Inorganic
Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84536 Bratislava, Slovakia
| | - Syed Awais Rouf
- NMR Research Unit, University of Oulu, P.O. Box 3000, FIN-90014 Oulu, Finland
| | - Juha Vaara
- NMR Research Unit, University of Oulu, P.O. Box 3000, FIN-90014 Oulu, Finland
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36
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37
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Damjanović M, Samuel PP, Roesky HW, Enders M. NMR analysis of an Fe(i)–carbene complex with strong magnetic anisotropy. Dalton Trans 2017; 46:5159-5169. [PMID: 28352888 DOI: 10.1039/c7dt00408g] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A paramagnetic, easy-plane anisotropic FeI complex, bearing cyclic-alkyl(amino) carbene (cAAC) ligands, is studied by means of NMR and DFT.
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Affiliation(s)
- Marko Damjanović
- Institute of Inorganic Chemistry
- Heidelberg University
- D-69120 Heidelberg
- Germany
| | - Prinson P. Samuel
- Universität Göttingen
- Institut für Anorganische Chemie
- Göttingen
- Germany
| | - Herbert W. Roesky
- Universität Göttingen
- Institut für Anorganische Chemie
- Göttingen
- Germany
| | - Markus Enders
- Institute of Inorganic Chemistry
- Heidelberg University
- D-69120 Heidelberg
- Germany
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38
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Benda L, Mareš J, Ravera E, Parigi G, Luchinat C, Kaupp M, Vaara J. Pseudo-Contact NMR Shifts over the Paramagnetic Metalloprotein CoMMP-12 from First Principles. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608829] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ladislav Benda
- Institut für Chemie, Theoretische Chemie; Technische Universität Berlin; Sekr. C7, Straße des 17. Juni 135 10623 Berlin Germany
- Institut des Sciences Analytiques; UMR 5280 CNRS/ ENS Lyon/ UCB Lyon 1; 5 rue de la Doua 69100 Villeurbanne France
| | - Jiří Mareš
- NMR Research Unit; University of Oulu; P.O. Box 3000 90014 Oulu Finland
| | - Enrico Ravera
- Magnetic Resonance Center; University of Florence and; Interuniversity Consortium for Magnetic Resonance of Metalloproteins; Sesto Fiorentino Italy
| | - Giacomo Parigi
- Magnetic Resonance Center; University of Florence and; Interuniversity Consortium for Magnetic Resonance of Metalloproteins; Sesto Fiorentino Italy
- Department of Chemistry; University of Florence; Sesto Fiorentino Italy
| | - Claudio Luchinat
- Magnetic Resonance Center; University of Florence and; Interuniversity Consortium for Magnetic Resonance of Metalloproteins; Sesto Fiorentino Italy
- Department of Chemistry; University of Florence; Sesto Fiorentino Italy
| | - Martin Kaupp
- Institut für Chemie, Theoretische Chemie; Technische Universität Berlin; Sekr. C7, Straße des 17. Juni 135 10623 Berlin Germany
| | - Juha Vaara
- NMR Research Unit; University of Oulu; P.O. Box 3000 90014 Oulu Finland
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39
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Benda L, Mareš J, Ravera E, Parigi G, Luchinat C, Kaupp M, Vaara J. Pseudo-Contact NMR Shifts over the Paramagnetic Metalloprotein CoMMP-12 from First Principles. Angew Chem Int Ed Engl 2016; 55:14713-14717. [PMID: 27781358 DOI: 10.1002/anie.201608829] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Indexed: 11/08/2022]
Abstract
Long-range pseudo-contact NMR shifts (PCSs) provide important restraints for the structure refinement of proteins when a paramagnetic metal center is present, either naturally or introduced artificially. Here we show that ab initio quantum-chemical methods and a modern version of the Kurland-McGarvey approach for paramagnetic NMR (pNMR) shifts in the presence of zero-field splitting (ZFS) together provide accurate predictions of all PCSs in a metalloprotein (high-spin cobalt-substituted MMP-12 as a test case). Computations of 314 13 C PCSs using g- and ZFS tensors based on multi-reference methods provide a reliable bridge between EPR-parameter- and susceptibility-based pNMR formalisms. Due to the high sensitivity of PCSs to even small structural differences, local structures based either on X-ray diffraction or on various DFT optimizations could be evaluated critically by comparing computed and experimental PCSs. Many DFT functionals provide insufficiently accurate structures. We also found the available 1RMZ PDB X-ray structure to exhibit deficiencies related to binding of a hydroxamate inhibitor. This has led to a newly refined PDB structure for MMP-12 (5LAB) that provides a more accurate coordination arrangement and PCSs.
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Affiliation(s)
- Ladislav Benda
- Institut für Chemie, Theoretische Chemie, Technische Universität Berlin, Sekr. C7, Straße des 17. Juni 135, 10623, Berlin, Germany.,Institut des Sciences Analytiques, UMR 5280 CNRS/ ENS Lyon/ UCB Lyon 1, 5 rue de la Doua, 69100, Villeurbanne, France
| | - Jiří Mareš
- NMR Research Unit, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland
| | - Enrico Ravera
- Magnetic Resonance Center, University of Florence and, Interuniversity Consortium for Magnetic Resonance of Metalloproteins, Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center, University of Florence and, Interuniversity Consortium for Magnetic Resonance of Metalloproteins, Sesto Fiorentino, Italy.,Department of Chemistry, University of Florence, Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center, University of Florence and, Interuniversity Consortium for Magnetic Resonance of Metalloproteins, Sesto Fiorentino, Italy.,Department of Chemistry, University of Florence, Sesto Fiorentino, Italy
| | - Martin Kaupp
- Institut für Chemie, Theoretische Chemie, Technische Universität Berlin, Sekr. C7, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Juha Vaara
- NMR Research Unit, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland
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40
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Remigio RD, Repisky M, Komorovsky S, Hrobarik P, Frediani L, Ruud K. Four-component relativistic density functional theory with the polarisable continuum model: application to EPR parameters and paramagnetic NMR shifts. Mol Phys 2016. [DOI: 10.1080/00268976.2016.1239846] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Roberto Di Remigio
- Department of Chemistry, Centre for Theoretical and Computational Chemistry, University of Tromsø– The Arctic University of Norway, Tromsø, Norway
| | - Michal Repisky
- Department of Chemistry, Centre for Theoretical and Computational Chemistry, University of Tromsø– The Arctic University of Norway, Tromsø, Norway
| | - Stanislav Komorovsky
- Department of Chemistry, Centre for Theoretical and Computational Chemistry, University of Tromsø– The Arctic University of Norway, Tromsø, Norway
| | - Peter Hrobarik
- Institut für Chemie, Technische Universität Berlin, Berlin, Germany
| | - Luca Frediani
- Department of Chemistry, Centre for Theoretical and Computational Chemistry, University of Tromsø– The Arctic University of Norway, Tromsø, Norway
| | - Kenneth Ruud
- Department of Chemistry, Centre for Theoretical and Computational Chemistry, University of Tromsø– The Arctic University of Norway, Tromsø, Norway
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41
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Gendron F, Autschbach J. Ligand NMR Chemical Shift Calculations for Paramagnetic Metal Complexes: 5f1 vs 5f2 Actinides. J Chem Theory Comput 2016; 12:5309-5321. [DOI: 10.1021/acs.jctc.6b00462] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Frédéric Gendron
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
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42
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Bühl M, Ashbrook SE, Dawson DM, Doyle RA, Hrobárik P, Kaupp M, Smellie IA. Paramagnetic NMR of Phenolic Oxime Copper Complexes: A Joint Experimental and Density Functional Study. Chemistry 2016; 22:15328-15339. [DOI: 10.1002/chem.201602567] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Michael Bühl
- University of St. Andrews; School of Chemistry and Centre of Magnetic Resonance, North Haugh; St Andrews, Fife KY16 9ST Scotland UK
| | - Sharon E. Ashbrook
- University of St. Andrews; School of Chemistry and Centre of Magnetic Resonance, North Haugh; St Andrews, Fife KY16 9ST Scotland UK
| | - Daniel M. Dawson
- University of St. Andrews; School of Chemistry and Centre of Magnetic Resonance, North Haugh; St Andrews, Fife KY16 9ST Scotland UK
| | - Rachel A. Doyle
- University of St. Andrews; School of Chemistry and Centre of Magnetic Resonance, North Haugh; St Andrews, Fife KY16 9ST Scotland UK
| | - Peter Hrobárik
- Technische Universität Berlin; Institut für Chemie; Strasse des 17. Juni 135 D-10623 Berlin Germany
| | - Martin Kaupp
- Technische Universität Berlin; Institut für Chemie; Strasse des 17. Juni 135 D-10623 Berlin Germany
| | - Iain A. Smellie
- University of St. Andrews; School of Chemistry and Centre of Magnetic Resonance, North Haugh; St Andrews, Fife KY16 9ST Scotland UK
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43
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Novotný J, Sojka M, Komorovsky S, Nečas M, Marek R. Interpreting the Paramagnetic NMR Spectra of Potential Ru(III) Metallodrugs: Synergy between Experiment and Relativistic DFT Calculations. J Am Chem Soc 2016; 138:8432-45. [DOI: 10.1021/jacs.6b02749] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jan Novotný
- CEITEC − Central European Institute
of Technology, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
| | - Martin Sojka
- CEITEC − Central European Institute
of Technology, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
| | - Stanislav Komorovsky
- Centre for
Theoretical and Computational Chemistry, Department of Chemistry, UiT − The Arctic University of Norway, N-9037 Tromsø, Norway
| | - Marek Nečas
- CEITEC − Central European Institute
of Technology, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
| | - Radek Marek
- CEITEC − Central European Institute
of Technology, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ − 62500 Brno, Czech Republic
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Martin B, Autschbach J. Kohn–Sham calculations of NMR shifts for paramagnetic 3d metal complexes: protocols, delocalization error, and the curious amide proton shifts of a high-spin iron(ii) macrocycle complex. Phys Chem Chem Phys 2016; 18:21051-68. [DOI: 10.1039/c5cp07667f] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ligand chemical shifts (pNMR shifts) are analyzed using DFT. A large difference in the amide proton shifts of a high-spin Fe(ii) complex arises from O → Fe dative bonding which only transfers β spin density to the metal.
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Affiliation(s)
- Bob Martin
- Department of Chemistry
- University at Buffalo
- State University of New York
- Buffalo
- USA
| | - Jochen Autschbach
- Department of Chemistry
- University at Buffalo
- State University of New York
- Buffalo
- USA
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45
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Vaara J, Rouf SA, Mareš J. Magnetic couplings in the chemical shift of paramagnetic NMR. J Chem Theory Comput 2015; 11:4840-9. [PMID: 26574272 DOI: 10.1021/acs.jctc.5b00656] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We apply the Kurland-McGarvey (J. Magn. Reson. 1970, 2, 286) theory for the NMR shielding of paramagnetic molecules, particularly its special case limited to the ground-state multiplet characterized by zero-field splitting (ZFS) interaction of the form S·D·S. The correct formulation for this problem was recently presented by Soncini and Van den Heuvel (J. Chem. Phys. 2013, 138, 054113). With the effective electron spin quantum number S, the theory involves 2S+1 states, of which all but one are low-lying excited states, between which magnetic couplings take place by Zeeman and hyperfine interactions. We investigate these couplings as a function of temperature, focusing on both the high- and low-temperature behaviors. As has been seen in work by others, the full treatment of magnetic couplings is crucial for a realistic description of the temperature behavior of NMR shielding up to normal measurement temperatures. At high temperatures, depending on the magnitude of ZFS, the effect of magnetic couplings diminishes, and the Zeeman and hyperfine interactions become effectively averaged in the thermally occupied states of the multiplet. At still higher temperatures, the ZFS may be omitted altogether, and the shielding properties may be evaluated using a doublet-like formula, with all the 2S+1 states becoming effectively degenerate at the limit of vanishing magnetic field. We demonstrate these features using first-principles calculations of Ni(II), Co(II), Cr(II), and Cr(III) complexes, which have ZFS of different sizes and signs. A non-monotonic inverse temperature dependence of the hyperfine shift is predicted for axially symmetric integer-spin systems with a positive D parameter of ZFS. This is due to the magnetic coupling terms that are proportional to kT at low temperatures, canceling the Curie-type 1/kT prefactor of the hyperfine shielding in this case.
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Affiliation(s)
- Juha Vaara
- NMR Research Group, University of Oulu , P.O. Box 3000, FIN-90014 Oulu, Finland
| | - Syed Awais Rouf
- NMR Research Group, University of Oulu , P.O. Box 3000, FIN-90014 Oulu, Finland
| | - Jiří Mareš
- NMR Research Group, University of Oulu , P.O. Box 3000, FIN-90014 Oulu, Finland
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Gendron F, Sharkas K, Autschbach J. Calculating NMR Chemical Shifts for Paramagnetic Metal Complexes from First-Principles. J Phys Chem Lett 2015; 6:2183-2188. [PMID: 26266589 DOI: 10.1021/acs.jpclett.5b00932] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Paramagnetic effects on NMR shifts (pNMR) for paramagnetic metal complexes are calculated from first-principles, without recourse to spin Hamiltonian parameters. A newly developed code based on complete active space (CAS) and restricted active space (RAS) techniques in conjunction with treating spin-orbit (SO) coupling via state interaction is applied to (13)C NMR shifts of actinyl tris-carbonate complexes, specifically [UO2(CO3)3](5-) and [NpO2(CO3)3](4-). The experimental pNMR shifts as well as the sizable difference of the (13)C NMR shift for these iso-electronic species are well reproduced by the calculations. Approximations to the pNMR shift equations using spin Hamiltonian parameters or the magnetic susceptibility are calculated for the same systems at the same level of theory, and it is shown how the approximations relate to the ab initio data.
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Affiliation(s)
- Frédéric Gendron
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Kamal Sharkas
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
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47
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NMR Calculations for Paramagnetic Molecules and Metal Complexes. ANNUAL REPORTS IN COMPUTATIONAL CHEMISTRY 2015. [DOI: 10.1016/bs.arcc.2015.09.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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