Dataset Information

Fully Automated Quantum-Chemistry-Based Computation of Spin-Spin-Coupled Nuclear Magnetic Resonance Spectra.

ABSTRACT: We present a composite procedure for the quantum-chemical computation of spin-spin-coupled ¹ H?NMR spectra for general, flexible molecules in solution that is based on four main steps, namely conformer/rotamer ensemble (CRE) generation by the fast tight-binding method GFN-xTB and a newly developed search algorithm, computation of the relative free energies and NMR parameters, and solving the spin Hamiltonian. In this way the NMR-specific nuclear permutation problem is solved, and the correct spin symmetries are obtained. Energies, shielding constants, and spin-spin couplings are computed at state-of-the-art DFT levels with continuum solvation. A few (in)organic and transition-metal complexes are presented, and very good, unprecedented agreement between the theoretical and experimental spectra was achieved. The approach is routinely applicable to systems with up to 100-150 atoms and may open new avenues for the detailed (conformational) structure elucidation of, for example, natural products or drug molecules.

SUBMITTER: Grimme S

PROVIDER: S-EPMC5698732 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Fully Automated Quantum-Chemistry-Based Computation of Spin-Spin-Coupled Nuclear Magnetic Resonance Spectra.

Grimme Stefan S Bannwarth Christoph C Dohm Sebastian S Hansen Andreas A Pisarek Jana J Pracht Philipp P Seibert Jakob J Neese Frank F

Angewandte Chemie (International ed. in English) 20171011 46

We present a composite procedure for the quantum-chemical computation of spin-spin-coupled <sup>1</sup> H NMR spectra for general, flexible molecules in solution that is based on four main steps, namely conformer/rotamer ensemble (CRE) generation by the fast tight-binding method GFN-xTB and a newly developed search algorithm, computation of the relative free energies and NMR parameters, and solving the spin Hamiltonian. In this way the NMR-specific nuclear permutation problem is solved, and the ...[more]

PMID: 28906074

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Dataset Information

Fully Automated Quantum-Chemistry-Based Computation of Spin-Spin-Coupled Nuclear Magnetic Resonance Spectra.

Publications

Fully Automated Quantum-Chemistry-Based Computation of Spin-Spin-Coupled Nuclear Magnetic Resonance Spectra.

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