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Mastrorilli P, Todisco S, Bagno A, Gallo V, Latronico M, Fortuño C, Gudat D. Multinuclear Solid-State NMR and DFT Studies on Phosphanido-Bridged Diplatinum Complexes. Inorg Chem 2015; 54:5855-63. [PMID: 26001215 DOI: 10.1021/acs.inorgchem.5b00627] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Piero Mastrorilli
- Dipartimento
di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica
(DICATECh), Politecnico di Bari, Via Orabona 4, I-70125 Bari, Italy
- Consiglio
Nazionale delle Ricerche, Istituto di Chimica dei Composti Organometallici (ICCOM-CNR), Via Orabona 4, 70125 Bari, Italy
| | - Stefano Todisco
- Dipartimento
di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica
(DICATECh), Politecnico di Bari, Via Orabona 4, I-70125 Bari, Italy
| | - Alessandro Bagno
- Dipartimento
di Scienze Chimiche, Università di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Vito Gallo
- Dipartimento
di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica
(DICATECh), Politecnico di Bari, Via Orabona 4, I-70125 Bari, Italy
| | - Mario Latronico
- Dipartimento
di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica
(DICATECh), Politecnico di Bari, Via Orabona 4, I-70125 Bari, Italy
- Consiglio
Nazionale delle Ricerche, Istituto di Chimica dei Composti Organometallici (ICCOM-CNR), Via Orabona 4, 70125 Bari, Italy
| | - Consuelo Fortuño
- Departamento
de Química Inorgánica, Instituto de Síntesis
Química y Catálisis Homogénea, Universidad de Zaragoza-C.S.I.C., E-50009 Zaragoza, Spain
| | - Dietrich Gudat
- Institut
für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring
55, 70569 Stuttgart, Germany
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Lucier BE, Reidel AR, Schurko RW. Multinuclear solid-state NMR of square-planar platinum complexes — Cisplatin and related systems. CAN J CHEM 2011. [DOI: 10.1139/v11-033] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Multinuclear solid-state nuclear magnetic resonance (SSNMR) experiments have been performed on cisplatin and four related square-planar compounds. The wideband uniform rate smooth truncation – Carr–Purcell–Meiboom–Gill (WURST–CPMG) pulse sequence was utilized in NMR experiments to acquire 195Pt, 14N, and 35Cl ultra-wideline NMR spectra of high quality. Standard Hahn-echo and magic-angle spinning 195Pt NMR experiments are also performed to refine extracted chemical shielding (CS) tensor parameters. Platinum magnetic shielding (MS) tensor orientations are calculated using both plane-wave density functional theory (DFT) and standard DFT methods. The tensor orientations are shown to be highly constrained by molecular symmetry elements, but also influenced to some degree by intermolecular interactions. 14N WURST–CPMG experiments were performed on three compounds and electric field gradient (EFG) parameters (the quadrupolar coupling constant, CQ, and the asymmetry parameter, ηQ) are reported. First principles calculations of the 14N EFG tensor parameters and orientations and affirm their dependence on the local hydrogen bonding environment. 35Cl WURST–CPMG experiments on cisplatin and transplatin are reported, using two different static magnetic fields to extract EFG and CS tensor parameters, and 35Cl EFG tensor magnitudes and orientations are predicted using first principles calculations. Transverse (T2) relaxation data for all nuclei are used to investigate heteronuclear dipolar relaxation mechanisms, as well as the nature of the local hydrogen bonding environments.
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Affiliation(s)
- Bryan E.G. Lucier
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B 3P4, Canada
| | - Alex R. Reidel
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B 3P4, Canada
| | - Robert W. Schurko
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B 3P4, Canada
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Bryce DL, Courchesne NMD, Perras FA. Measurement of delta(1)J((199)Hg, (31)P) in [HgPCy3(OAc)2]2 and relativistic ZORA DFT investigations of mercury-phosphorus coupling tensors. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2009; 36:182-191. [PMID: 20056396 DOI: 10.1016/j.ssnmr.2009.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 10/29/2009] [Accepted: 11/25/2009] [Indexed: 05/28/2023]
Abstract
Using 31P solid-state NMR spectroscopy, anisotropy in the indirect 199Hg-31P spin-spin coupling tensor (DeltaJ) for powdered [HgPCy3(OAc)2]2 (1) has been measured as 4700 +/- 300 Hz. Zeroth-order regular approximation (ZORA) density functional theory (DFT) calculations, including scalar and spin-orbit relativistic effects, performed on 1 and a series of other related compounds show that DeltaJ(199Hg, (31)P) arises entirely from the ZORA Fermi-contact-spin-dipolar cross term. The calculations validate assumptions made in the spectral analysis of 1 and in previous determinations of DeltaJ in powder samples, namely that J is axially symmetric and shares its principal axis system with the direct dipolar coupling tensor (D). Agreement between experiment and theory for various 199Hg, 31P spin-spin coupling anisotropies is reasonable; however, experimental values of 1J(199Hg, 31P)(iso) are significantly underestimated by the calculations. The most important improvements in the agreement were obtained as a result of including more of the crystal lattice in the model used for the calculations, e.g., a change of 43% was noted for 1J(199Hg, 31P)(iso) in [HgPPh3(NO3)2]2 depending on whether the two or three nearest nitrate ions are included in the model. Finally, we have written a computer program to simulate the effects of non-axial symmetry in J and of non-coincidence of the J and D on powder NMR spectra. Simulations clearly show that both of these effects have a pronounced impact on the 31P NMR spectrum of 199Hg-31P spin pairs, suggesting that the effects should be observable experimentally if a suitable compound can be identified.
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Affiliation(s)
- David L Bryce
- Department of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario, Canada K1N6N5.
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Harris KJ, Bryce DL, Wasylishen RE. NMR line shapes from AB spin systems in solids — The role of antisymmetric spin–spin coupling. CAN J CHEM 2009. [DOI: 10.1139/v09-089] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NMR parameters such as indirect nuclear spin–spin coupling (J), nuclear magnetic shielding (σ), direct dipolar coupling (D), and electric field gradient (V) are properly described by second-rank tensors. Each may be decomposed into isotropic, symmetric, and antisymmetric components; the number of these three components which may be nonzero is a distinguishing attribute of each interaction tensor. The rank-1 antisymmetric portion of J (Janti) holds the distinction of remaining the only nonzero part of these fundamental NMR interaction tensors which has never been observed experimentally. Accordingly, effects from Janti are usually ignored, but it is important to consider when this is valid. An experimental strategy for observing Janti in powdered samples of tightly coupled homonuclear spin pairs, based on ideas originally presented by Andrew and Farnell ( Mol. Phys. 1968, 15, 157 ), is described. The theory of Andrew and Farnell is extended to powder samples, and methods for analyzing NMR spectra from powdered samples are presented. It is found that, in certain rare cases, Janti has the potential to affect the NMR line shapes from AB spin systems, but that even in these systems, the most intense features of the spectra are not affected and may be analyzed independently of Janti. Furthermore, Janti will only have an observable effect on the NMR spectra when its magnitude is comparable with that of Jiso and with the difference in chemical shifts (in Hz) between the two sites. Finally, the first experimental attempts to measure Janti are reported, and experimental proof that no elements of Janti(119Sn,119Sn) in hexa(p-tolyl)ditin are larger than 2900 Hz is given. The benefits of modern double-quantum filtering NMR pulse sequences in isolating effects from Janti are also illustrated.
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Affiliation(s)
| | - David L. Bryce
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada
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Tang JA, Kogut E, Norton D, Lough AJ, McGarvey BR, Fekl U, Schurko RW. Impact of reduction on the properties of metal bisdithiolenes: multinuclear solid-state NMR and structural studies on Pt(tfd)2 and its reduced forms. J Phys Chem B 2009; 113:3298-313. [PMID: 19236015 DOI: 10.1021/jp807530d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Transition-metal dithiolene complexes have interesting structures and fascinating redox properties, making them promising candidates for a number of applications, including superconductors, photonic devices, chemical sensors, and catalysts. However, not enough is known about the molecular electronic origins of these properties. Multinuclear solid-state NMR spectroscopy and first-principles calculations are used to examine the molecular and electronic structures of the redox series [Pt(tfd)(2)](z-) (tfd = S(2)C(2)(CF(3))(2); z = 0, 1, 2; the anionic species have [NEt(4)](+) countercations). Single-crystal X-ray structures for the neutral (z = 0) and the fully reduced forms (z = 2) were obtained. The two species have very similar structures but differ slightly in their intraligand bond lengths. (19)F-(195)Pt CP/CPMG and (195)Pt magic-angle spinning (MAS) NMR experiments are used to probe the diamagnetic (z = 0, 2) species, revealing large platinum chemical shielding anisotropies (CSA) with distinct CS tensor properties, despite the very similar structural features of these species. Density functional theory (DFT) calculations are used to rationalize the large platinum CSAs and CS tensor orientations of the diamagnetic species using molecular orbital (MO) analysis, and are used to explain their distinct molecular electronic structures in the context of the NMR data. The paramagnetic species (z = 1) is examined using both EPR spectroscopy and (13)C and (19)F MAS NMR spectroscopy. Platinum g-tensor components were determined by using solid-state EPR experiments. The unpaired electron spin densities at (13)C and (19)F nuclei were measured by employing variable-temperature (13)C and (19)F NMR experiments. DFT and ab initio calculations are able to qualitatively reproduce the experimentally measured g-tensor components and spin densities. The combination of experimental and theoretical data confirm localization of unpaired electron density in the pi-system of the dithiolene rings.
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Affiliation(s)
- Joel A Tang
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada
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Kogut E, Tang JA, Lough AJ, Widdifield CM, Schurko RW, Fekl U. Neutral high-potential nickel triad bisdithiolenes: structure and solid-state NMR properties of Pt[S2C2(CF3)2]2. Inorg Chem 2007; 45:8850-2. [PMID: 17054340 DOI: 10.1021/ic0614972] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
X-ray crystallography and solid-state NMR techniques were used to determine the structure and 195Pt NMR chemical shift (CS) tensor of Pt[S2C2(CF3)2]2. This is the first reported crystal structure of a highly oxidizing (CN- or CF3-substituted) neutral bis(dithiolene) complex of a Ni triad metal in its pure form. The 195Pt NMR CS tensor is highly anisotropic and asymmetric; the latter property is attributed to the noninnocent nature of the ligand. The tensor components and orientation are determined with density functional theory calculations.
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Affiliation(s)
- Elzbieta Kogut
- Department of Chemical and Physical Sciences, UTM, 3359 Mississauga Road North, University of Toronto, Mississauga, Ontario, Canada
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Siegel R, Nakashima TT, Wasylishen RE. Application of Multiple-Pulse Experiments to Characterize Broad NMR Chemical-Shift Powder Patterns from Spin-1/2 Nuclei in the Solid State. J Phys Chem B 2004. [DOI: 10.1021/jp031048c] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Renée Siegel
- Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Thomas T. Nakashima
- Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Roderick E. Wasylishen
- Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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Bowmaker GA, Harris RK, Apperley DC. Solid-State (199)Hg MAS NMR and Vibrational Spectroscopic Studies of Dimercury(I) Compounds. Inorg Chem 1999; 38:4956-4962. [PMID: 11671237 DOI: 10.1021/ic9905648] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The solid-state (199)Hg MAS NMR spectra of Hg(2)X(2) (X = Cl, SCN, NCO, CH(3)CO(2), CF(3)CO(2)) have been measured, and the infrared and Raman spectra of these compounds have been recorded and analyzed to further characterize them and to assist in the interpretation of the NMR data. Spinning-sideband analysis has been used to determine the (199)Hg shielding anisotropy and asymmetry parameters Deltasigma and eta from the solid-state (199)Hg MAS NMR spectra. In contrast to the case of the corresponding mercury(II) compounds, the shielding anisotropy is found to be relatively insensitive to the nature of the X group. This is consistent with the view that the electronic environment of the Hg atom in the mercury(I) compounds is dominated by the Hg-Hg bond. The changes in the (199)Hg shielding parameters from the mercury(II) to the corresponding mercury(I) compounds, as well as the changes in these parameters in the mercury(I) compounds with changes in X, can be interpreted in terms of variations in the local paramagnetic contribution to the shielding tensor.
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Affiliation(s)
- Graham A. Bowmaker
- Departments of Chemistry, University of Auckland, Private Bag 92019, Auckland, New Zealand, and University of Durham, South Road, Durham DH1 3LE, United Kingdom
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Bowmaker GA, Churakov AV, Harris RK, Howard JAK, Apperley DC. Solid-State 199Hg MAS NMR Studies of Mercury(II) Thiocyanate Complexes and Related Compounds. Crystal Structure of Hg(SeCN)2. Inorg Chem 1998. [DOI: 10.1021/ic9700112] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Graham A. Bowmaker
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom
| | - Andrei V. Churakov
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom
| | - Robin K. Harris
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom
| | - Judith A. K. Howard
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom
| | - David C. Apperley
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom
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