1
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Bruder F, Weigend F, Franzke YJ. Application of the Adiabatic Connection Random Phase Approximation to Electron-Nucleus Hyperfine Coupling Constants. J Phys Chem A 2024; 128:7298-7310. [PMID: 39163640 PMCID: PMC11372758 DOI: 10.1021/acs.jpca.4c03794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/22/2024]
Abstract
The electron-nucleus hyperfine coupling constant is a challenging property for density functional methods. For accurate results, hybrid functionals with a large amount of exact exchange are often needed and there is no clear "one-for-all" functional which describes the hyperfine coupling interaction for a large set of nuclei. To alleviate this unfavorable situation, we apply the adiabatic connection random phase approximation (RPA) in its post-Kohn-Sham fashion to this property as a first test. For simplicity, only the Fermi-contact and spin-dipole terms are calculated within the nonrelativistic and the scalar-relativistic exact two-component framework. This requires to solve a single coupled-perturbed Kohn-Sham equation to evaluate the relaxed density matrix, which comes with a modest increase in computational demands. RPA performs remarkably well and substantially improves upon its Kohn-Sham (KS) starting point while also reducing the dependence on the KS reference. For main-group systems, RPA outperforms global, range-separated, and local hybrid functionals─at similar computational costs. For transition-metal compounds and lanthanide complexes, a similar performance as for hybrid functionals is observed. In contrast, related post-Hartree-Fock methods such as Møller-Plesset perturbation theory or CC2 perform worse than semilocal density functionals.
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Affiliation(s)
- Florian Bruder
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Florian Weigend
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Yannick J Franzke
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
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2
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Pitman SJ, Evans AK, Ireland RT, Lempriere F, McKemmish LK. Benchmarking Basis Sets for Density Functional Theory Thermochemistry Calculations: Why Unpolarized Basis Sets and the Polarized 6-311G Family Should Be Avoided. J Phys Chem A 2023; 127:10295-10306. [PMID: 37982604 DOI: 10.1021/acs.jpca.3c05573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2023]
Abstract
Basis sets are a crucial but often largely overlooked choice in setting up quantum chemistry calculations. The choice of the basis set can be critical in determining the accuracy and calculation time of your quantum chemistry calculations. Clear recommendations based on thorough benchmarking are essential but not readily available currently. This study investigates the relative quality of basis sets for general properties by benchmarking basis set performance for a diverse set of 139 reactions (from the diet-150-GMTKN55 data set). In our analysis, we find the distributions of errors are often significantly non-Gaussian, meaning that the joint consideration of median errors, mean absolute errors, and outlier statistics is helpful to provide a holistic understanding of basis set performance. Our direct comparison of performance between most modern basis sets provides quantitative evidence for basis set recommendations that broadly align with the established understanding of basis set experts and is evident in the design of modern basis sets. For example, while zeta is a good measure of quality, it is not the only determining factor for an accurate calculation with unpolarized double- and triple-ζ basis sets (like 6-31G and 6-311G) having very poor performance. Appropriate use of polarization functions (e.g., 6-31G*) is essential to obtain the accuracy offered by double- or triple-ζ basis sets. In our study, the best performances for double- and triple-ζ basis sets are 6-31++G** and pcseg-2, respectively. However, the performances of singly polarized double-ζ and doubly polarized triple-ζ basis sets are quite similar with one key exception: the polarized 6-311G basis set family has poor parametrization, which means its performance is more like a double-ζ than a triple-ζ basis set. All versions of the 6-311G basis set family should be avoided entirely for valence chemistry calculations moving forward.
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Affiliation(s)
- Samuel J Pitman
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
| | - Alicia K Evans
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
| | - Robbie T Ireland
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
| | - Felix Lempriere
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
| | - Laura K McKemmish
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
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3
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Bormann N, Ward JS, Bergmann AK, Wenz P, Rissanen K, Gong Y, Hatz WB, Burbaum A, Mulks FF. Diiminium Nucleophile Adducts Are Stable and Convenient Strong Lewis Acids. Chemistry 2023; 29:e202302089. [PMID: 37427889 DOI: 10.1002/chem.202302089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 07/08/2023] [Accepted: 07/10/2023] [Indexed: 07/11/2023]
Abstract
Strong Lewis acids are essential tools for manifold chemical procedures, but their scalable deployment is limited by their costs and safety concerns. We report a scalable, convenient, and inexpensive synthesis of stable diiminium-based reagents with a Lewis acidic carbon centre. Coordination with pyridine donors stabilises these centres; the 2,2'-bipyridine adduct shows a chelation effect at carbon. Due to high fluoride, hydride, and oxide affinities, the diiminium pyridine adducts are promising soft and hard Lewis acids. They effectively produce acylpyridinium salts from carboxylates that can acylate amines to give amides and imides even from electronically intractable coupling partners.
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Affiliation(s)
- Niklas Bormann
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Jas S Ward
- Department of Chemistry, University of Jyvaskyla, P. O. Box. 35, Survontie 9 B, 40014, Jyväskylä, Finland
| | - Ann Kathrin Bergmann
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Paula Wenz
- Department of Chemistry, University of Jyvaskyla, P. O. Box. 35, Survontie 9 B, 40014, Jyväskylä, Finland
| | - Kari Rissanen
- Department of Chemistry, University of Jyvaskyla, P. O. Box. 35, Survontie 9 B, 40014, Jyväskylä, Finland
| | - Yiwei Gong
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Wolf-Benedikt Hatz
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Alexander Burbaum
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
| | - Florian F Mulks
- Institute for Organic Chemistry (iOC), RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany
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4
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Rusakov YY, Rusakova IL. New pecJ- n ( n = 1, 2) Basis Sets for Selenium Atom Purposed for the Calculations of NMR Spin-Spin Coupling Constants Involving Selenium. Int J Mol Sci 2023; 24:ijms24097841. [PMID: 37175548 PMCID: PMC10178039 DOI: 10.3390/ijms24097841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/19/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
We present new compact pecJ-n (n = 1, 2) basis sets for the selenium atom developed for the quantum-chemical calculations of NMR spin-spin coupling constants (SSCCs) involving selenium nuclei. These basis sets were obtained at the second order polarization propagator approximation with coupled cluster singles and doubles amplitudes (SOPPA(CCSD)) level with the property-energy consistent (PEC) method, which was introduced in our previous papers. The existing SSCC-oriented selenium basis sets are rather large in size, while the PEC method gives more compact basis sets that are capable of providing accuracy comparable to that reached using the property-oriented basis sets of larger sizes generated with a standard even-tempered technique. This is due to the fact that the PEC method is very different in its essence from the even-tempered approaches. It generates new exponents through the total optimization of angular spaces of trial basis sets with respect to the property under consideration and the total molecular energy. New basis sets were tested on the coupled cluster singles and doubles (CCSD) calculations of SSCCs involving selenium in the representative series of molecules, taking into account relativistic, solvent, and vibrational corrections. The comparison with the experiment showed that the accuracy of the results obtained with the pecJ-2 basis set is almost the same as that provided by a significantly larger basis set, aug-cc-pVTZ-J, while that achieved with a very compact pecJ-1 basis set is only slightly inferior to the accuracy provided by the former.
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Affiliation(s)
- Yuriy Yu Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia
| | - Irina L Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia
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5
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Rusakova IL, Rusakov YY. On the Utmost Importance of the Basis Set Choice for the Calculations of the Relativistic Corrections to NMR Shielding Constants. Int J Mol Sci 2023; 24:6231. [PMID: 37047204 PMCID: PMC10094374 DOI: 10.3390/ijms24076231] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
The investigation of the sensitivity of the relativistic corrections to the NMR shielding constants (σ) to the configuration of angular spaces of the basis sets used on the atoms of interest was carried out within the four-component density functional theory (DFT). Both types of relativistic effects were considered, namely the so-called heavy atom on light atom and heavy atom on heavy atom effects, though the main attention was paid to the former. As a main result, it was found that the dependence of the relativistic corrections to σ of light nuclei (exemplified here by 1H and 13C) located in close vicinity to a heavy atom (exemplified here by In, Sn, Sb, Te, and I) on the basis set used on the light spectator atom was very much in common with that of the Fermi-contact contribution to the corresponding nonrelativistic spin-spin coupling constant (J). In general, it has been shown that the nonrelativistic J-oriented and σ-oriented basis sets, artificially saturated in the tight s-region, provided much better accuracy than the standard nonrelativistic σ-oriented basis sets when calculating the relativistic corrections to the NMR shielding constants of light nuclei at the relativistic four-component level of the DFT theory.
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Affiliation(s)
- Irina L. Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia;
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Gleeson R, Andersen CL, Rapta P, Machata P, Christensen JB, Hammerich O, Sauer SPA. A Combined Experimental and Theoretical Study of ESR Hyperfine Coupling Constants for N,N,N',N'-Tetrasubstituted p-Phenylenediamine Radical Cations. Int J Mol Sci 2023; 24:3447. [PMID: 36834859 PMCID: PMC9967363 DOI: 10.3390/ijms24043447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/26/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
A test set of N,N,N',N'-tetrasubstituted p-phenylenediamines are experimentally explored using ESR (electron spin resonance) spectroscopy and analysed from a computational standpoint thereafter. This computational study aims to further aid structural characterisation by comparing experimental ESR hyperfine coupling constants (hfccs) with computed values calculated using ESR-optimised "J-style" basis sets (6-31G(d,p)-J, 6-31G(d,p)-J, 6-311++G(d,p)-J, pcJ-1, pcJ-2 and cc-pVTZ-J) and hybrid-DFT functionals (B3LYP, PBE0, TPSSh, ωB97XD) as well as MP2. PBE0/6-31g(d,p)-J with a polarised continuum solvation model (PCM) correlated best with the experiment, giving an R2 value of 0.8926. A total of 98% of couplings were deemed satisfactory, with five couplings observed as outlier results, thus degrading correlation values significantly. A higher-level electronic structure method, namely MP2, was sought to improve outlier couplings, but only a minority of couples showed improvement, whilst the remaining majority of couplings were negatively degraded.
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Affiliation(s)
- Ronan Gleeson
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Cecilie L. Andersen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Peter Rapta
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovakia
| | - Peter Machata
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovakia
| | - Jørn B. Christensen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Ole Hammerich
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Stephan P. A. Sauer
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
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7
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New pecJ-n (n = 1, 2) Basis Sets for High-Quality Calculations of Indirect Nuclear Spin–Spin Coupling Constants Involving 31P and 29Si: The Advanced PEC Method. Molecules 2022; 27:molecules27196145. [PMID: 36234706 PMCID: PMC9573013 DOI: 10.3390/molecules27196145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/14/2022] [Accepted: 09/16/2022] [Indexed: 11/21/2022] Open
Abstract
In this paper, we presented new J-oriented basis sets, pecJ-n (n = 1, 2), for phosphorus and silicon, purposed for the high-quality correlated calculations of the NMR spin–spin coupling constants involving these nuclei. The pecJ-n basis sets were generated using the modified version of the property-energy consistent (PEC) method, which was introduced in our earlier paper. The modifications applied to the original PEC procedure increased the overall accuracy and robustness of the generated basis sets in relation to the diversity of electronic systems. Our new basis sets were successfully tested on a great number of spin–spin coupling constants, involving phosphorus or/and silicon, calculated within the SOPPA(CCSD) method. In general, it was found that our new pecJ-1 and pecJ-2 basis sets are very efficient, providing the overall accuracy that can be characterized by MAEs of about 3.80 and 1.98 Hz, respectively, against the benchmark data obtained with a large dyall.aae4z+ basis set of quadruple-ζ quality.
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8
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Rusakov YY, Rusakova IL. New pecS- n ( n = 1, 2) basis sets for quantum chemical calculations of the NMR chemical shifts of H, C, N, and O nuclei. J Chem Phys 2022; 156:244112. [DOI: 10.1063/5.0096907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This paper demonstrates the performance of our previously suggested property-energy consistent method on the example of the generation of effective basis sets, pecS-1 and pecS-2, suited for the calculation of hydrogen, carbon, nitrogen, and oxygen chemical shifts. The new basis sets were successfully approbated in the GIAO-DFT calculations of the chemical shifts of 35 molecules using six different functionals. The pecS-1 basis set demonstrated very good accuracy, which makes this small basis set an effective means for the large-scale computations. At the same time, the pecS-2 basis set also gave very accurate results, thus putting it on a par with the other commensurate basis sets suited for the chemical shifts calculations.
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Affiliation(s)
- Yuriy Yu. Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russian Federation
| | - Irina L. Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russian Federation
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9
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Quantum Chemical Approaches to the Calculation of NMR Parameters: From Fundamentals to Recent Advances. MAGNETOCHEMISTRY 2022. [DOI: 10.3390/magnetochemistry8050050] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Quantum chemical methods for the calculation of indirect NMR spin–spin coupling constants and chemical shifts are always in progress. They never stay the same due to permanently developing computational facilities, which open new perspectives and create new challenges every now and then. This review starts from the fundamentals of the nonrelativistic and relativistic theory of nuclear magnetic resonance parameters, and gradually moves towards the discussion of the most popular common and newly developed methodologies for quantum chemical modeling of NMR spectra.
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10
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Windom ZW, Perera A, Bartlett RJ. Benchmarking isotropic hyperfine coupling constants using (QTP) DFT functionals and coupled cluster theory. J Chem Phys 2022; 156:094107. [DOI: 10.1063/5.0069928] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Significant effort has been devoted to benchmarking isotropic hyperfine coupling constants for both wavefunction and density-based approaches in recent years, as accurate theoretical predictions aid the fitting of experimental model Hamiltonians. However, literature examining the predictive quality of a Density Functional Theory (DFT) functional abiding by the Bartlett IP condition is absent. In an attempt to rectify this, we report isotropic hyperfine coupling constant predictions of 24 commonly used DFT functionals on a total of 56 radicals, with the intent of exploring the successes and failures of the Quantum Theory Project (QTP) line of DFT functionals (i.e., CAM-QTP00, CAM-QTP01, CAM-QTP02, and QTP17) for this property. Included in this benchmark study are both small and large organic radicals as well as transition metal complexes, all of which have been studied to some extent in prior work. Subsequent coupled-cluster singles and doubles (CCSD) and CCSD withperturbative triples [CCSD(T)] calculations on small and large organic radicals show modest improvement as compared to prior work and offer an additional avenue for evaluation of DFT functional performance. We find that the QTP17 and CAM-QTP00 functionals consistently underperform, despite being parameterized to satisfy an IP eigenvalue condition primarily focused on inner shell electrons. On the other hand, the CAM-QTP01 functional is the most accurate functional in both organic radical datasets. Furthermore, both CAM-QTP01 and CAM-QTP02 are the most accurate functionals tested on the transition metal dataset. A significant portion of functionals were found to have comparable errors (within 5–15 MHz), but the hybrid class of DFT functionals maintains a consistently optimal balance between accuracy and precision across all datasets.
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Affiliation(s)
- Zachary W. Windom
- Quantum Theory Project, University of Florida, Gainesville, Florida 32611-8435, USA
| | - Ajith Perera
- Quantum Theory Project, University of Florida, Gainesville, Florida 32611-8435, USA
| | - Rodney J. Bartlett
- Quantum Theory Project, University of Florida, Gainesville, Florida 32611-8435, USA
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11
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Steinmann C, Sauer SPA. The aug-cc-pVTZ-J basis set for the p-block fourth-row elements Ga, Ge, As, Se, and Br. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:1134-1145. [PMID: 33929770 DOI: 10.1002/mrc.5166] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
The aug-cc-pVTZ-J basis set family is extended to include the fourth-row p-block elements Ga, Ge, As, Se, and Br. We use the established approach outlined by Sauer and coworkers (J. Chem. Phys. 115, 1324 [2001], J. Chem. Phys. 133, 054308 [2010], J. Chem. Theory Comput. 7, 4070 [2011], and J. Chem. Theory Comput. 7, 4077 [2011]) where the completely uncontracted aug-cc-pVTZ basis set is saturated with tight s-, p-, d-, and f-functions to form the aug-cc-pVTZ-Juc basis set for the tested elements. The saturation is carried out on the simplest hydrides possible for the tested elements GaH, GeH4 , AsH3 , H2 Se, and HBr until an improvement is less than 0.01% for all s-, p-, and d-functions added. f-Functions are added to an improvement less than or equal to 1.0% due to the computational expense these functions add. The saturated aug-cc-pVTZ-Juc (26s16p12d5f) is then recontracted using the molecular orbital coefficients from self-consistent field calculations on the simple hydrides to improve computational efficiency. During contraction of the basis set, we observe that the linear hydrogen bromide molecule has a slower convergence than the other tested molecules which sets a limit on the accuracy obtained. All calculations with the contracted aug-cc-pVTZ-J [17s10p7d5f] gives results that are within 1.0% of the uncontracted results at considerable computational savings.
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Affiliation(s)
- Casper Steinmann
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
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12
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Kjellgren ER, Jensen HJA. Multi-configurational short-range density functional theory can describe spin-spin coupling constants of transition metal complexes. J Chem Phys 2021; 155:084102. [PMID: 34470359 DOI: 10.1063/5.0059128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The multi-configurational short-range (sr) density functional theory has been extended to the calculation of indirect spin-spin coupling constants (SSCCs) for nuclear magnetic resonance spectroscopy. The performance of the new method is compared to Kohn-Sham density functional theory and the ab initio complete active space self-consistent field for a selected set of molecules with good reference values. Two density functionals have been considered, the local density approximation srLDA and srPBE from the GGA class of functionals. All srDFT calculations are of Hartree-Fock-type HF-srDFT or complete active space-type CAS-srDFT. In all cases, the calculated SSCC values are of the same quality for srLDA and srPBE functionals, suggesting that one should use the computationally cost-effective srLDA functionals in applications. For all the calculated SSCCs in organic compounds, the best choice is HF-srDFT; the more expensive CAS-srDFT does not provide better values for these single-reference molecules. Fluorine is a challenge; in particular, the FF, FC, and FO couplings have much higher statistical errors than the rest. For SSCCs involving fluorine and a metal atom CAS-srDFT with singlet, generalized Tamm-Dancoff approximation is needed to get good SSCC values although the reference ground state is not a multi-reference case. For VF6 -1, all other considered models fail blatantly.
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Affiliation(s)
- Erik Rosendahl Kjellgren
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Hans Jørgen Aagaard Jensen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
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13
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Rusakov YY, Rusakova IL. An efficient method for generating property-energy consistent basis sets. New pecJ- n ( n = 1, 2) basis sets for high-quality calculations of indirect nuclear spin-spin coupling constants involving 1H, 13C, 15N, and 19F nuclei. Phys Chem Chem Phys 2021; 23:14925-14939. [PMID: 34223856 DOI: 10.1039/d1cp01984h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This paper presents a new method of generating property-energy consistent (PEC) basis sets that can be applied to any arbitrary molecular property. The PEC method generates a basis set that is optimized for the molecular property under interest, providing the least possible total molecular energy. The main algorithm of the PEC approach involves Monte Carlo simulations to generate random exponents in the predetermined range. In this work, the PEC method is introduced in the example of generation of new pecJ-n (n = 1, 2) basis sets suited for high-quality correlated calculations of indirect nuclear spin-spin coupling constants involving the most popular NMR-active nuclei: 1H, 13C, 15N, and 19F.
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Affiliation(s)
- Yuriy Yu Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russian Federation.
| | - Irina L Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russian Federation.
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14
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Rusakov YY, Rusakova IL. Efficient J-oriented tin basis sets for the correlated calculations of indirect nuclear spin-spin coupling constants. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:713-722. [PMID: 33439515 DOI: 10.1002/mrc.5132] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/30/2020] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
New J-oriented tin basis sets, acvXz-J (X = 2, 3, 4), have been developed at the level of the second-order polarization propagator approximation with the coupled-cluster single and double amplitudes, SOPPA (CCSD), for the purpose of correlated calculations of indirect nuclear spin-spin coupling constants involving tin nucleus. High-quality coupled-cluster calculations of several tin-proton and tin-carbon spin-spin coupling constants, performed with one of the newly developed basis sets, namely, the acv3z-J, taking into account relativistic, solvent, and vibrational corrections showed that the acv3z-J basis set is capable to provide reliable results, as compared with the experimental data.
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Affiliation(s)
- Yuriy Yu Rusakov
- Siberian Branch of the Russian Academy of Sciences, A. E. Favorsky Irkutsk Institute of Chemistry, Irkutsk, Russian Federation
| | - Irina L Rusakova
- Siberian Branch of the Russian Academy of Sciences, A. E. Favorsky Irkutsk Institute of Chemistry, Irkutsk, Russian Federation
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15
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Theibich YA, Sauer SP, Leggio LL, Hedegård ED. Estimating the accuracy of calculated electron paramagnetic resonance hyperfine couplings for a lytic polysaccharide monooxygenase. Comput Struct Biotechnol J 2020; 19:555-567. [PMID: 33510861 PMCID: PMC7807142 DOI: 10.1016/j.csbj.2020.12.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/11/2020] [Accepted: 12/13/2020] [Indexed: 11/07/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are enzymes that bind polysaccharides followed by an (oxidative) disruption of the polysaccharide surface, thereby boosting depolymerization. The binding process between the LPMO catalytic domain and polysaccharide is key to the mechanism and establishing structure-function relationships for this binding is therefore crucial. The hyperfine coupling constants (HFCs) from EPR spectroscopy have proven useful for this purpose. Unfortunately, EPR does not provide direct structural data and therefore the experimental EPR parameters have to be supported with parameters calculated with density functional theory. Yet, calculated HFCs are extremely sensitive to the employed computational setup. Using the LPMO Ls(AA9)A catalytic domain, we here quantify the importance of several choices in the computational setup, ranging from the use of specialized basis, the underlying structures, and the employed exchange-correlation functional. We show that specialized basis sets are an absolute necessity, and also that care has to be taken in the optimization of the underlying structure: only by allowing large parts of the protein around the active site to structurally relax could we obtain results that uniformly reproduced experimental trends. We compare our results to previously published X-ray structures and experimental HFCs for Ls(AA9)A as well as to recent experimental/theoretical results for another (AA10) family of LPMOs.
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Affiliation(s)
- Yusuf A. Theibich
- Department of Chemistry, University of University, Copenhagen, Denmark
| | | | - Leila Lo Leggio
- Department of Chemistry, University of University, Copenhagen, Denmark
| | - Erik D. Hedegård
- Division of Theoretical Chemistry, Lund University, Chemical Centre, P. O. Box 124, SE-221 00 Lund, Sweden
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Rusakova IL, Rusakov YY. Correlated ab initio calculations of one-bond 31 P 77 Se and 31 P 125 Te spin-spin coupling constants in a series of PSe and PTe systems accounting for relativistic effects (part 2). MAGNETIC RESONANCE IN CHEMISTRY : MRC 2020; 58:929-940. [PMID: 32453871 DOI: 10.1002/mrc.5058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/19/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
Synthetic chalcogen-phosphorus chemistry permanently makes new challenges to computational Nuclear Magnetic Resonance (NMR) spectroscopy, which has proven to be a powerful tool of structural analysis of chalcogen-phosphorus compounds. This paper reports on the calculations of one-bond 31 P77 Se and 31 P125 Te NMR spin-spin coupling constants (SSCCs) in the series of phosphine selenides and tellurides. The applicability of the combined computational approach to the one-bond 31 P77 Se and 31 P125 Te SSCCs, incorporating the composite nonrelativistic scheme, built of high-accuracy correlated SOPPA (CC2) and Coupled Cluster Single and Double (CCSD) methods and the Density Functional Theory (DFT) relativistic corrections (four-component level), was examined against the experiment and another scheme based on the four-component relativistic DFT method. A special J-oriented basis set (acv3z-J) for selenium and tellurium atoms, developed previously by the authors, was used throughout the NMR calculations in this work at the first time. The proposed computational methodologies (combined and 'pure') provided a reasonable accuracy for 31 P77 Se and 31 P125 Te SSCCs against experimental data, characterizing by the mean absolute percentage errors of about 4% and 1%, and 12% and 8% for selenium and tellurium species, respectively. The present study reports typical relativistic corrections to 77 Se31 P and 125 Te31 P SSCCs, calculated within the four-component DFT formalism for a broad series of tertiary phosphine selenides and tellurides with different substituents at phosphorus.
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Affiliation(s)
- Irina L Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, Irkutsk, 664033, Russia
| | - Yuriy Yu Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, Irkutsk, 664033, Russia
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17
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18
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Hansen PE, Saeed BA, Rutu RS, Kupka T. One-bond 1 J( 15 N,H) coupling constants at sp 2 -hybridized nitrogen of Schiff bases, enaminones and similar compounds: A theoretical study. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2020; 58:750-762. [PMID: 32415997 DOI: 10.1002/mrc.5052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/07/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
1 J(15 N,H) coupling constants for enaminones and NH-forms of intramolecularly hydrogen-bonded Schiff bases as model compounds for sp2 -hybridized nitrogen atoms are evaluated using density functional theory (DFT) to find the optimal functionals and basis sets. Ammonia is used as a test molecule and its one-bond coupling constant is compared with experiment. A methylamine Schiff base of a truncated molecule of gossypol is used for checking the performance of selected B3LYP, O3LYP, PBE, BHandH, and APFD density functionals and standard, modified, and dedicated basis sets for coupling constants. Both in vacuum and in chloroform, modeled by the simple continuum model of solvent, the modified basis sets predict significantly better the 1 J(15 N,H) value in ammonia and in the methylamine Schiff base of a truncated molecule of gossypol than the standard basis sets. This procure is then used on a broad set of intramolecularly hydrogen-bonded molecules, and a good correlation between calculated and experimental one-bond NH coupling constants is obtained. The 1 J(15 N,H) couplings are slightly overestimated. The calculated data show for hydrogen-bonded NH interatomic distances that the calculated values depend on the NH bond lengths. The shorter the bond lengths, the larger the 1 J(15 N,H). A useful correlation between 1 J(15 N,H) and NH bond length is derived that enables realistic predictions of one-bond NH coupling constants. The calculations reproduce experimentally observed trends for the studied molecules.
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Affiliation(s)
- Poul Erik Hansen
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | - Bahjat A Saeed
- Department of Chemistry, College of Education for Pure Sciences, University of Basrah, Iraq
| | - Rita S Rutu
- Department of Pharmaceutical Chemistry, College of Pharmacy, University of Basrah, Iraq
| | - Teobald Kupka
- Faculty of Chemistry, University of Opole, Opole, Poland
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Elguero J, Alkorta I, Del Bene JE. Calculated coupling constants 1 J(X-Y) and 1 K(X-Y), and fundamental relationships among the reduced coupling constants for molecules H m X-YH n , with X, Y ═ 1 H, 7 Li, 9 Be, 11 B, 13 C, 15 N, 17 O, 19 F, 31 P, 33 S, and 35 Cl. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2020; 58:727-732. [PMID: 32247293 DOI: 10.1002/mrc.5026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/24/2020] [Accepted: 03/26/2020] [Indexed: 06/11/2023]
Abstract
Equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) calculations have been performed to determine coupling constants 1 J(X-Y) for 65 molecules Hm X-YHn , with X,Y ═ 1 H, 7 Li, 9 Be, 11 B, 13 C, 15 N, 17 O, 19 F, 31 P, 33 S, and 35 Cl. The computed 1 J(X-Y) values are in good agreement with available experimental data. The reduced coupling constants 1 K(X-Y) have been derived from 1 J(X-Y) by removing the dependence on the magnetogyric ratios of X and Y. Patterns are found for the reduced coupling constants on a 1 K(X-Y) surface that are related to the positions of X and Y in the periodic table.
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Affiliation(s)
- José Elguero
- Instituto de Química Médica (CSIC), Madrid, Spain
| | - Ibon Alkorta
- Instituto de Química Médica (CSIC), Madrid, Spain
| | - Janet E Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio, USA
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20
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Rusakov YY, Rusakova IL. Hierarchical Basis Sets for the Calculation of Nuclear Magnetic Resonance Spin–Spin Coupling Constants Involving Either Selenium or Tellurium Nuclei. J Phys Chem A 2019; 123:6564-6571. [DOI: 10.1021/acs.jpca.9b05276] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuriy Yu. Rusakov
- Siberian Branch of the Russian Academy of Sciences, A. E. Favorsky Irkutsk Institute of Chemistry, Favorsky St. 1, 664033 Irkutsk, Russian Federation
| | - Irina L. Rusakova
- Siberian Branch of the Russian Academy of Sciences, A. E. Favorsky Irkutsk Institute of Chemistry, Favorsky St. 1, 664033 Irkutsk, Russian Federation
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21
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Lino JBDR, Ramalho TC. Exploring Through-Space Spin-Spin Couplings for Quantum Information Processing: Facing the Challenge of Coherence Time and Control Quantum States. J Phys Chem A 2019; 123:1372-1379. [PMID: 30673241 DOI: 10.1021/acs.jpca.8b09425] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nuclear magnetic resonance (NMR) is a powerful tool for studying quantum information processing (QIP). Recently quantum technologies have been proposed to overcome the challenges in large-scale NMR QIP. Furthermore, computational chemistry can promote its improvement. Nuclear spins-1/2 are natural qubits and have been used in most NMR quantum computation experiments. However, molecules that enable many qubits NMR QIP implementations should meet some requirements regarding their spectroscopic properties. Exceptionally large through-space (TS) P-P spin-spin coupling constants (SSCC or J) observed in 1,8-diphosphanaphthalenes (PPN) and in naphtho[1,8- cd]-1,2-dithiole phenylphosphines (NTP) were proposed and investigated to provide more accurate control within large-scale NMR QIP. Spectroscopic properties of PPN and NTP derivatives were explored by theoretical strategies using locally dense basis sets (LDBS). 31P chemical shifts (δ) calculated at the B3LYP/aug-cc-pVTZ-J level and TS P-P SSCCs at the PBE1PBE/pcJ-2 (LDBS-1) level are very close to the experimental data for the PPN molecule. Differently, for the NTP dimer, PBE1PBE/pcJ-2 (LDBS-2) predicts more accurate 31P δ, whereas PBE1PBE/Def2-TZVP (LDBS-1) forecasts more accurate TS P-P SSCCs. From our results, PPNo-F, PPNo-ethyl, and PPNo-NH2 were the best candidates for NMR QIP, in which the large TS SSCCS could face the need of long-time quantum gates implementations. Therefore, it could overcome natural limitations concerning the development of large-scale NMR.
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Affiliation(s)
| | - Teodorico Castro Ramalho
- Chemistry Department , Federal University of Lavras , 37200-000 Lavras , MG Brazil.,Center for Basic and Applied Research, Faculty of Informatics and Management , University Hradec Kralove , 50003 Hradec Kralove , Czech Republic
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22
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On the development of the exact two-component relativistic method for calculating indirect NMR spin-spin coupling constants. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2018.09.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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23
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Nepel A, Viesser RV, Tormena CF. 1 J CH Coupling in Benzaldehyde Derivatives: Ortho Substitution Effect. ACS OMEGA 2019; 4:1494-1503. [PMID: 31459414 PMCID: PMC6648193 DOI: 10.1021/acsomega.8b03035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 01/08/2019] [Indexed: 05/30/2023]
Abstract
The natural J-coupling (NJC) method is applied to analyze the Fermi contact contribution of the NMR spin-spin coupling constant decomposing this contribution in terms of natural localized molecular orbitals. We investigated the influence of the basis set on the NJC analysis for the formyl group coupling constant (1 J CHf) of benzaldehyde derivatives. NJC and other NBO analyses, like steric and natural Coulombic energy, were chosen to explain the influence of electron-donating and electron-withdrawing groups on 1 J CHf for some substituted benzaldehydes (Me, OH, OMe, F, Cl, Br, I, and NO2). For the ortho derivatives, electronegative substituents near the C-Hf bond increase the 1 J CHf coupling. This effect could be related to an increase in formyl carbon s character and changes in the carbon and hydrogen natural charges. This indicates that the substituents in ortho have a proximity effect on 1 J CHf coupling mainly of electrostatic origin instead of the expected hyperconjugative interactions.
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Jaszuński M, Świder P, Sauer SPA. Through-space spin–spin coupling constants involving fluorine: benchmarking DFT functionals. Mol Phys 2019. [DOI: 10.1080/00268976.2018.1563726] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Michał Jaszuński
- Institute of Organic Chemistry, Polish Academy of Sciences, Warszawa, Poland
| | - Paweł Świder
- Institute of Organic Chemistry, Polish Academy of Sciences, Warszawa, Poland
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25
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Ambroise MA, Jensen F. Probing Basis Set Requirements for Calculating Core Ionization and Core Excitation Spectroscopy by the Δ Self-Consistent-Field Approach. J Chem Theory Comput 2018; 15:325-337. [DOI: 10.1021/acs.jctc.8b01071] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Frank Jensen
- Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
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26
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Pagola GI, Larsen MAB, Ferraro M, Sauer SPA. The influence of relativistic effects on nuclear magnetic resonance spin-spin coupling constant polarizabilities of H2O2, H2S2, H2Se2, and H2Te2. J Comput Chem 2018; 39:2589-2600. [DOI: 10.1002/jcc.25648] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 09/18/2018] [Accepted: 09/19/2018] [Indexed: 12/23/2022]
Affiliation(s)
- Gabriel I. Pagola
- Departamento de Física, Facultad de Ciencias Exactas y Naturales; Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria; Pabellón 1, (1428) Buenos Aires Argentina
| | - Martin A. B. Larsen
- Department of Chemistry; University of Copenhagen; Universitetsparken 5, DK-2100 Copenhagen Ø Denmark
| | - Marta Ferraro
- Departamento de Física, Facultad de Ciencias Exactas y Naturales; Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria; Pabellón 1, (1428) Buenos Aires Argentina
| | - Stephan P. A. Sauer
- Department of Chemistry; University of Copenhagen; Universitetsparken 5, DK-2100 Copenhagen Ø Denmark
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27
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Krivdin LB. Theoretical calculations of carbon-hydrogen spin-spin coupling constants. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 108:17-73. [PMID: 30538048 DOI: 10.1016/j.pnmrs.2018.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/09/2018] [Accepted: 10/11/2018] [Indexed: 06/09/2023]
Abstract
Structural applications of theoretical calculations of carbon-hydrogen spin-spin coupling constants are reviewed covering papers published mainly during the last 10-15 years with a special emphasis on the most notable studies of hybridization, substitution and stereoelectronic effects together with the investigation of hydrogen bonding and intermolecular interactions. The wide scope of different applications of calculated carbon-hydrogen couplings in the structural elucidation of particular classes of organic and bioorganic molecules is reviewed, concentrating mainly on saturated, unsaturated, aromatic and heteroaromatic compounds and their functional derivatives, as well as on natural compounds and carbohydrates. The review is dedicated to Professor Emeritus Michael Barfield in view of his invaluable pioneering contribution to this field.
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Affiliation(s)
- Leonid B Krivdin
- A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia.
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28
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Aggelund PA, Sauer SPA, Jensen F. Development of polarization consistent basis sets for spin-spin coupling constant calculations for the atoms Li, Be, Na, and Mg. J Chem Phys 2018; 149:044117. [PMID: 30068157 DOI: 10.1063/1.5034109] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The pcJ-n basis set, optimized for spin-spin coupling constant calculations using density functional theory methods, are expanded to also include the s-block elements Li, Be, Na, and Mg, by studying several small molecules containing these elements. This is done by decontracting the underlying pc-n basis sets, followed by augmentation with additional tight functions. As was the case for the p-block elements, the convergence of the results can be significantly improved by augmentation with tight s-functions. For the p-block elements, additional tight functions of higher angular momentum were also needed, but this is not the case for the s-block elements. A search for the optimum contraction scheme is carried out using the criterion that the contraction error should be lower than the inherent error of the uncontracted pcJ-n relative to the uncontracted pcJ-4 basis set. A large search over possible contraction schemes is done for the Li2 and Na2 molecules, and based on this search contracted pcJ-n basis sets for the four atoms are recommended. This work shows that it is more difficult to contract the pcJ-n basis sets, than the underlying pc-n basis sets. However, it also shows that the pcJ-n basis sets for Li and Be can be more strongly contracted than the pcJ-n basis sets for the p-block elements. For Na and Mg, the contractions are to the same degree as for the p-block elements.
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Affiliation(s)
- Patrick A Aggelund
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark
| | - Frank Jensen
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
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29
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Faber R, Sauer SPA. On the convergence of the ccJ-pVXZ and pcJ-n basis sets in CCSD calculations of nuclear spin–spin coupling constants: some difficult cases. Theor Chem Acc 2018. [DOI: 10.1007/s00214-018-2217-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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30
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How reliable are Minnesota density functionals for modeling phosphorus–hydrogen NMR spin–spin coupling constants? Theor Chem Acc 2017. [DOI: 10.1007/s00214-017-2182-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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31
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Mendt M, Barth B, Hartmann M, Pöppl A. Low-temperature binding of NO adsorbed on MIL-100(Al)—A case study for the application of high resolution pulsed EPR methods and DFT calculations. J Chem Phys 2017; 147:224701. [DOI: 10.1063/1.4995551] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Matthias Mendt
- Felix-Bloch-Institut für Festkörperphysik, Universität Leipzig, Linnéstr. 5, 04103 Leipzig, Germany
| | - Benjamin Barth
- Erlangen Catalysis Resource Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Martin Hartmann
- Erlangen Catalysis Resource Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Andreas Pöppl
- Felix-Bloch-Institut für Festkörperphysik, Universität Leipzig, Linnéstr. 5, 04103 Leipzig, Germany
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Affiliation(s)
- Balazs Nagy
- Department of Chemistry; Aarhus University; Aarhus Denmark
| | - Frank Jensen
- Department of Chemistry; Aarhus University; Aarhus Denmark
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33
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Faber R, Sauer SPA, Gauss J. Importance of Triples Contributions to NMR Spin-Spin Coupling Constants Computed at the CC3 and CCSDT Levels. J Chem Theory Comput 2017; 13:696-709. [PMID: 27992184 DOI: 10.1021/acs.jctc.6b01003] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present the first analytical implementation of CC3 second derivatives using the spin-unrestricted approach. This allows, for the first time, the calculation of nuclear spin-spin coupling constants (SSCC) relevant to NMR spectroscopy at the CC3 level of theory in a fully analytical manner. CC3 results for the SSCCs of a number of small molecules and their fluorine substituted derivatives are compared with the corresponding coupled cluster singles and doubles (CCSD) results obtained using specialized basis sets. For one-bond couplings the change when going from CCSD to CC3 is typically 1-3%, but much higher corrections were found for 1JCN in FCN, 15.7%, and 1JOF in OF2, 6.4%. The changes vary significantly in the case of multibond couplings, with differences of up to 10%, and even 13.6% for 3JFH in fluoroacetylene. Calculations at the coupled cluster singles, doubles, and triples (CCSDT) level indicate that the most important contributions arising from connected triple excitations in the coupled cluster expansion are accounted for at the CC3 level. Thus, we believe that the CC3 method will become the standard approach for the calculation of reference values of nuclear spin-spin coupling constants.
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Affiliation(s)
- Rasmus Faber
- Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Jürgen Gauss
- Institut für Physikalische Chemie, Universität Mainz , 55099 Mainz, Germany
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34
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Faber R, Buczek A, Kupka T, Sauer SPA. On the convergence of zero-point vibrational corrections to nuclear shieldings and shielding anisotropies towards the complete basis set limit in water. Mol Phys 2016. [DOI: 10.1080/00268976.2016.1210831] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Rasmus Faber
- Department of Chemistry, University of Copenhagen, Copenhagen Ø, Denmark
| | - Aneta Buczek
- Faculty of Chemistry, University of Opole, Opole, Poland
| | - Teobald Kupka
- Faculty of Chemistry, University of Opole, Opole, Poland
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35
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Buczek A, Makowski M, Jewgiński M, Latajka R, Kupka T, Broda MA. Toward engineering efficient peptidomimetics. Screening conformational landscape of two modified dehydroaminoacids. Biopolymers 2016; 101:28-40. [PMID: 23606332 DOI: 10.1002/bip.22264] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 04/12/2013] [Indexed: 11/11/2022]
Abstract
Effective peptidomimetics should posses structural rigidity and appropriate interaction pattern leading to potential spatial and electronic matching to the target receptor site. Rational design of such small bioactive molecules could push chemical synthesis and molecular modeling toward faster progress in medicinal chemistry. Conformational properties of N-t-butoxycarbonyl-glycine-(E/Z)-dehydrophenylalanine N',N'-dimethylamides (Boc-Gly-(E/Z)-ΔPhe-NMe2 ) in chloroform were studied by NMR and IR spectroscopy. The experimental findings were supported by extensive calculations at DFT(B3LYP, M06-2X) and MP2 levels of theory and the β-turn tendency for both isomers of the studied dipeptide were determined in vacuum and in solution. The theoretical data and experimental IR results were used as an additional information for the NMR-based determination of the detailed solution conformations of the peptides. The obtained results reveal that N-methylation of C-terminal amide group changes dramatically the conformational properties of studied dehydropeptides. Theoretical conformational analysis reveals that the tendency to adopt β-turn conformations is much weaker for the N-methylated Z isomer (Boc-Gly-(Z)-ΔPhe-NMe2 ), both in vacuum and in polar environment. On the contrary, N-methylated E isomer (Boc-Gly-(E)-ΔPhe-NMe2 ) can easily adopt β-turn conformation, but the backbone torsion angles (φ1, ψ1, φ2, ψ2) are off the limits for common β-turn types.
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Affiliation(s)
- Aneta Buczek
- Department of Physical Chemistry and Molecular Modeling, Faculty of Chemistry, University of Opole, Oleska 48, 45-052, Opole, Poland
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Alipour M, Fallahzadeh P. First principles optimally tuned range-separated density functional theory for prediction of phosphorus–hydrogen spin–spin coupling constants. Phys Chem Chem Phys 2016; 18:18431-40. [DOI: 10.1039/c6cp02648f] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The novel optimally tuned range-separated approximations for predicting NMR spin–spin coupling constants are proposed and benchmarked numerically.
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Affiliation(s)
- Mojtaba Alipour
- Department of Chemistry
- College of Sciences
- Shiraz University
- Shiraz
- Iran
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37
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Zarycz MNC, Provasi PF, Sauer SPA. On the truncation of the number of excited states in density functional theory sum-over-states calculations of indirect spin spin coupling constants. J Chem Phys 2015; 143:244107. [PMID: 26723651 DOI: 10.1063/1.4937572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
It is investigated, whether the number of excited (pseudo)states can be truncated in the sum-over-states expression for indirect spin-spin coupling constants (SSCCs), which is used in the Contributions from Localized Orbitals within the Polarization Propagator Approach and Inner Projections of the Polarization Propagator (IPPP-CLOPPA) approach to analyzing SSCCs in terms of localized orbitals. As a test set we have studied the nine simple compounds, CH4, NH3, H2O, SiH4, PH3, SH2, C2H2, C2H4, and C2H6. The excited (pseudo)states were obtained from time-dependent density functional theory (TD-DFT) calculations with the B3LYP exchange-correlation functional and the specialized core-property basis set, aug-cc-pVTZ-J. We investigated both how the calculated coupling constants depend on the number of (pseudo)states included in the summation and whether the summation can be truncated in a systematic way at a smaller number of states and extrapolated to the total number of (pseudo)states for the given one-electron basis set. We find that this is possible and that for some of the couplings it is sufficient to include only about 30% of the excited (pseudo)states.
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Affiliation(s)
- M Natalia C Zarycz
- Department of Physics, University of Northeastern - CONICET, Av. Libertad 5500, Corrientes W3404AAS, Argentina
| | - Patricio F Provasi
- Department of Physics, University of Northeastern - CONICET, Av. Libertad 5500, Corrientes W3404AAS, Argentina
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
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38
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Reid DM, Kobayashi R, Collins MA. Systematic Study of Locally Dense Basis Sets for NMR Shielding Constants. J Chem Theory Comput 2015; 10:146-52. [PMID: 26579898 DOI: 10.1021/ct4007579] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper presents a systematic study of partitioning schemes for locally dense basis sets in the context of NMR shielding calculations. The partitionings explored were based exclusively on connectivity and utilized the basis sets from the pcS-n series. Deviations from pcS-4 shieldings were calculated for a set of 28 organic molecules at the HF, B3LYP, and KT3 levels of theory, with the primary goal being the determination of an efficient scheme that achieves maximal deviations of 0.1 ppm for (1)H and 1 ppm for (13)C. Both atom based and group based divisions of basis sets were examined, with the latter providing the most promising results. It is demonstrated that for the systems studied, at least pcS-1 is required for all parts of the molecule. This, coupled with pcS-3 on the group of interest and pcS-2 on the adjacent groups, is sufficient to achieve the desired level of accuracy at a minimal computational expense. In addition, the suitability of the pcS-n basis sets for post-SCF methods was confirmed through a comparison with other standard basis sets at the MP2 level.
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Affiliation(s)
- David M Reid
- Research School of Chemistry, The Australian National University , Acton ACT 0200, Australia
| | - Rika Kobayashi
- Australian National University Supercomputer Facility, The Australian National University , Acton ACT 0200, Australia
| | - Michael A Collins
- Research School of Chemistry, The Australian National University , Acton ACT 0200, Australia
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39
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McKemmish LK, Gilbert ATB. Accurate Electron Densities at Nuclei Using Small Ramp-Gaussian Basis Sets. J Chem Theory Comput 2015; 11:3679-83. [PMID: 26574451 DOI: 10.1021/acs.jctc.5b00528] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Electron densities at nuclei are difficult to calculate accurately with all-Gaussian basis sets because they lack an electron-nuclear cusp. The newly developed mixed ramp-Gaussian basis sets, such as R-31G, possess electron-nuclear cusps due to the presence of ramp functions in the basis. The R-31G basis set is a general-purpose mixed ramp-Gaussian basis set modeled on the 6-31G basis set. The prediction of electron densities at nuclei using R-31G basis sets for Li-F outperforms Dunning, Pople, and Jensen general purpose all-Gaussian basis sets of triple-ζ quality or lower and the cc-pVQZ basis set. It is of similar quality to the specialized pcJ-0 basis set which was developed with partial decontraction of core functions and extra high exponent s-Gaussians to predict electron density at the nucleus. These results show significant advantages in the properties of mixed ramp-Gaussian basis sets compared to all-Gaussian basis sets.
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Affiliation(s)
- Laura K McKemmish
- Department of Physics and Astronomy, University College London , London WC1E 6BT, United Kingdom.,Research School of Chemistry, Australian National University , Canberra 2601, Australia
| | - Andrew T B Gilbert
- Research School of Chemistry, Australian National University , Canberra 2601, Australia
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40
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Alipour M. In search of the appropriate theoretically justified mixing coefficient in parameter-free hybrid functionals for computing the NMR parameters. RSC Adv 2015. [DOI: 10.1039/c4ra13186j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The parameter-free hybrid density functionals, with theoretically justified mixing coefficients, are recommended to predict the NMR parameters.
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Affiliation(s)
- Mojtaba Alipour
- Department of Chemistry
- College of Sciences
- Shiraz University
- Shiraz
- Iran
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41
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Ingemar Olsen J, Sauer SPA, Marcus Pedersen C, Bols M. Exploring the relationship between the conformation and pKa: can a pKa value be used to determine the conformational equilibrium? Org Biomol Chem 2015; 13:3116-21. [DOI: 10.1039/c4ob02630f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the first time it is shown that the pKa directly reflects the conformational equilibrium of conformers.
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Affiliation(s)
| | | | | | - Mikael Bols
- Department of Chemistry
- University of Copenhagen
- 2100 Copenhagen Ø
- Denmark
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42
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Jensen F. Segmented Contracted Basis Sets Optimized for Nuclear Magnetic Shielding. J Chem Theory Comput 2014; 11:132-8. [DOI: 10.1021/ct5009526] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Frank Jensen
- Department
of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
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43
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Rusakova IL, Rusakov YY, Krivdin LB. Relativistic effects in the one-bond spin-spin coupling constants involving selenium. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2014; 52:500-510. [PMID: 25043341 DOI: 10.1002/mrc.4112] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 06/29/2014] [Accepted: 07/01/2014] [Indexed: 06/03/2023]
Abstract
One-bond spin-spin coupling constants involving selenium of seven different types, (1) J(Se,X), X = (1) H, (13) C, (15) N, (19) F, (29) Si, (31) P, and (77) Se, were calculated in the series of 14 representative compounds at the SOPPA(CCSD) level taking into account relativistic corrections evaluated both at the RPA and DFT levels of theory in comparison with experiment. Relativistic corrections were found to play a major role in the calculation of (1) J(Se,X) reaching as much as almost 170% of the total value of (1) J(Se,Se) and up to 60-70% for the rest of (1) J(Se,X). Scalar relativistic effects (Darwin and mass-velocity corrections) by far dominate over spin-orbit coupling in the total relativistic effects for all (1) J(Se,X). Taking into account relativistic corrections at both random phase approximation and density functional theory levels essentially improves the agreement of theoretical results with experiment. The most 'relativistic' (1) J(Se,Se) demonstrates a marked Karplus-type dihedral angle dependence with respect to the mutual orientation of the selenium lone pairs providing a powerful tool for stereochemical analysis of selenoorganic compounds.
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Affiliation(s)
- Irina L Rusakova
- Siberian Branch of the Russian Academy of Sciences, A. E. Favorsky Irkutsk Institute of Chemistry, Favorsky St. 1, 664033, Irkutsk, Russia
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44
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Garbacz P, Makulski W, Jaszuński M. The NMR spin–spin coupling constant1J(31P,1H) in an isolated PH3molecule. Phys Chem Chem Phys 2014; 16:21559-63. [DOI: 10.1039/c4cp02973a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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45
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Rusakova IL, Rusakov YY, Krivdin LB. Nonempirical calculations of the one-bond (29)Si-(13)C spin-spin coupling constants taking into account relativistic and solvent corrections. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2014; 52:413-421. [PMID: 24796525 DOI: 10.1002/mrc.4080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 04/08/2014] [Accepted: 04/09/2014] [Indexed: 06/03/2023]
Abstract
The computational study of the one-bond (29)Si-(13)C spin-spin coupling constants has been performed at the second-order polarization propagator approximation (SOPPA) level in the series of 60 diverse silanes with a special focus on the main factors affecting the accuracy of the calculation including the level of theory, the quality of the basis set, and the contribution of solvent and relativistic effects. Among three SOPPA-based methods, SOPPA(MP2), SOPPA(CC2), and SOPPA(CCSD), the best result was achieved with SOPPA(CCSD) when used in combination with Sauer's basis set aug-cc-pVTZ-J characterized by the mean absolute error of calculated coupling constants against the experiment of ca 2 Hz in the range of ca 200 Hz. The SOPPA(CCSD)/aug-cc-pVTZ-J method is recommended as the most accurate and effective computational scheme for the calculation of (1)J(Si,C). The slightly less accurate but essentially more economical SOPPA(MP2)/aug-cc-pVTZ-J and/or SOPPA(CC2)/aug-cc-pVTZ-J methods are recommended for larger molecular systems. It was shown that solvent and relativistic corrections do not play a major role in the computation of the total values of (1)J(Si,C); however, taking them into account noticeably improves agreement with the experiment. The rovibrational corrections are estimated to be of about 1 Hz or 1-1.5% of the total value of (1)J(Si,C).
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Affiliation(s)
- Irina L Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St 1, 664033, Irkutsk, Russia
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46
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Caputo MC, Provasi PF, Benitez L, Georg HC, Canuto S, Coutinho K. Monte Carlo–Quantum Mechanics Study of Magnetic Properties of Hydrogen Peroxide in Liquid Water. J Phys Chem A 2014; 118:6239-47. [DOI: 10.1021/jp411303n] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- María Cristina Caputo
- Departamento de Fı́sica, FCEN,
UBA and IFIBA, Conicet, Ciudad Universitaria, 1428, Buenos Aires, Argentina
| | - Patricio F. Provasi
- Department of Physics - IMIT, Northeastern University, Av. Libertad 5500, Corrientes, Argentina
| | - Lucía Benitez
- Department of Physics - IMIT, Northeastern University, Av. Libertad 5500, Corrientes, Argentina
| | - Herbert C. Georg
- Instituto
de Fı́sica, Universidade Federal de Goiás, CP 131, 74001-970 Goiânia, GO, Brazil
| | - Sylvio Canuto
- Instituto de Fı́sica, Universidade de São Paulo, CP
66318, 05315-970 São Paulo, Brazil
| | - Kaline Coutinho
- Instituto de Fı́sica, Universidade de São Paulo, CP
66318, 05315-970 São Paulo, Brazil
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47
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Pedersen MN, Hedegård ED, Kongsted J. Basis set error estimation for DFT calculations of electronic g-tensors for transition metal complexes. J Comput Chem 2014; 35:1809-14. [PMID: 25060998 DOI: 10.1002/jcc.23688] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 06/30/2014] [Accepted: 07/02/2014] [Indexed: 11/10/2022]
Abstract
We present a detailed study of the basis set dependence of electronic g-tensors for transition metal complexes calculated using Kohn-Sham density functional theory. Focus is on the use of locally dense basis set schemes where the metal is treated using either the same or a more flexible basis set than used for the ligand sphere. The performance of all basis set schemes is compared to the extrapolated complete basis set limit results. Furthermore, we test the performance of the aug-cc-pVTZ-J basis set developed for calculations of NMR spin-spin and electron paramagnetic resonance hyperfine coupling constants. Our results show that reasonable results can be obtain when using small basis sets for the ligand sphere, and very accurate results are obtained when an aug-cc-pVTZ basis set or similar is used for all atoms in the complex.
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Affiliation(s)
- Morten N Pedersen
- Department of Physics Chemistry Pharmacy, University of Southern Denmark, DK-5230, Odense M, Denmark
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48
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Wałęsa R, Ptak T, Siodłak D, Kupka T, Broda MA. Experimental and theoretical NMR studies of interaction between phenylalanine derivative and egg yolk lecithin. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2014; 52:298-305. [PMID: 24639342 DOI: 10.1002/mrc.4064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/18/2014] [Accepted: 02/28/2014] [Indexed: 06/03/2023]
Abstract
The interaction of phenylalanine diamide (Ac-Phe-NHMe) with egg yolk lecithin (EYL) in chloroform was studied by (1)H and (13)C NMR. Six complexes EYL-Ac-Phe-NHMe, stabilized by N-H···O or/and C-H···O hydrogen bonds, were optimized at M06-2X/6-31G(d,p) level. The assignment of EYL and Ac-Phe-NHMe NMR signals was supported using GIAO (gauge including atomic orbital) NMR calculations at VSXC and B3LYP level of theory combined with STO-3Gmag basis set. Results of our study indicate that the interaction of peptides with lecithin occurs mainly in the polar 'head' of the lecithin. Additionally, the most probable lecithin site of H-bond interaction with Ac-Phe-NHMe is the negatively charged oxygen in phosphate group that acts as proton acceptor.
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Affiliation(s)
- Roksana Wałęsa
- Faculty of Chemistry, University of Opole, Oleska 48 Str., 45-052, Opole, Poland
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49
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Rusakov YY, Rusakova IL, Krivdin LB. Full four-component relativistic calculations of the one-bond 77Se-13C spin-spin coupling constants in the series of selenium heterocycles and their parent open-chain selenides. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2014; 52:214-221. [PMID: 24549877 DOI: 10.1002/mrc.4053] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 01/19/2014] [Accepted: 01/23/2014] [Indexed: 06/03/2023]
Abstract
Four-component relativistic calculations of (77)Se-(13)C spin-spin coupling constants have been performed in the series of selenium heterocycles and their parent open-chain selenides. It has been found that relativistic effects play an essential role in the selenium-carbon coupling mechanism and could result in a contribution of as much as 15-25% of the total values of the one-bond selenium-carbon spin-spin coupling constants. In the overall contribution of the relativistic effects to the total values of (1)J(Se,C), the scalar relativistic corrections (negative in sign) by far dominate over the spin-orbit ones (positive in sign), the latter being of less than 5%, as compared to the former (ca 20%). A combination of nonrelativistic second-order polarization propagator approach (CC2) with the four-component relativistic density functional theory scheme is recommended as a versatile tool for the calculation of (1)J(Se,C). Solvent effects in the values of (1)J(Se,C) calculated within the polarizable continuum model for the solvents with different dielectric constants (ε 2.2-78.4) are next to negligible decreasing negative (1)J(Se,C) in absolute value by only about 1 Hz. The use of the locally dense basis set approach applied herewith for the calculation of (77)Se-(13)C spin-spin coupling constants is fully justified resulting in a dramatic decrease in computational cost with only 0.1-0.2-Hz loss of accuracy.
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Affiliation(s)
- Yury Yu Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033, Irkutsk, Russia
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50
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Rusakov YY, Krivdin LB, Østerstrøm FF, Sauer SPA, Potapov VA, Amosova SV. First example of a high-level correlated calculation of the indirect spin-spin coupling constants involving tellurium: tellurophene and divinyl telluride. Phys Chem Chem Phys 2014; 15:13101-13107. [PMID: 23824065 DOI: 10.1039/c3cp51462e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This paper documents the very first example of a high-level correlated calculation of spin-spin coupling constants involving tellurium taking into account relativistic effects, vibrational corrections and solvent effects for medium sized organotellurium molecules. The (125)Te-(1)H spin-spin coupling constants of tellurophene and divinyl telluride were calculated at the SOPPA and DFT levels, in good agreement with experimental data. A new full-electron basis set, av3z-J, for tellurium derived from the "relativistic" Dyall's basis set, dyall.av3z, and specifically optimized for the correlated calculations of spin-spin coupling constants involving tellurium was developed. The SOPPA method shows a much better performance compared to DFT, if relativistic effects calculated within the ZORA scheme are taken into account. Vibrational and solvent corrections are next to negligible, while conformational averaging is of prime importance in the calculation of (125)Te-(1)H spin-spin couplings. Based on the performed calculations at the SOPPA(CCSD) level, a marked stereospecificity of geminal and vicinal (125)Te-(1)H spin-spin coupling constants originating in the orientational lone pair effect of tellurium has been established, which opens a new guideline in organotellurium stereochemistry.
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Affiliation(s)
- Yury Yu Rusakov
- A.E. Favorsky Irkutsk Institute of Chemistry, Russian Academy of Sciences, Siberian Branch, 1 Favorsky St., 664033 Irkutsk, Russia.
| | - Leonid B Krivdin
- A.E. Favorsky Irkutsk Institute of Chemistry, Russian Academy of Sciences, Siberian Branch, 1 Favorsky St., 664033 Irkutsk, Russia.
| | - Freja F Østerstrøm
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Vladimir A Potapov
- A.E. Favorsky Irkutsk Institute of Chemistry, Russian Academy of Sciences, Siberian Branch, 1 Favorsky St., 664033 Irkutsk, Russia.
| | - Svetlana V Amosova
- A.E. Favorsky Irkutsk Institute of Chemistry, Russian Academy of Sciences, Siberian Branch, 1 Favorsky St., 664033 Irkutsk, Russia.
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