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NMR crystallography of amino acids.
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SYSNO ASEP 0584468 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název NMR crystallography of amino acids. Tvůrce(i) Chaloupecká, Ema (UOCHB-X) ORCID
Tyrpekl, V. (CZ)
Bártová, Kateřina (UOCHB-X)
Nishiyama, Y. (JP)
Dračínský, Martin (UOCHB-X) RID, ORCIDZdroj.dok. Solid State Nuclear Magnetic Resonance. - : Elsevier - ISSN 0926-2040
Roč. 130, April (2024), s. 101921Poč.str. 10 s. Jazyk dok. eng - angličtina Země vyd. GB - Velká Británie Klíč. slova solid-state NMR spectroscopy ; DFT calculations ; amino acids ; polymorphism ; disorder CEP GA22-15374S GA ČR - Grantová agentura ČR Způsob publikování Omezený přístup Institucionální podpora UOCHB-X - RVO:61388963 UT WOS 001218319200001 EID SCOPUS 85186520819 DOI 10.1016/j.ssnmr.2024.101921 Anotace The development of NMR crystallography methods requires a reliable database of chemical shifts measured for systems with known crystal structure. We measured and assigned carbon and hydrogen chemical shifts of twenty solid natural amino acids of known polymorphic structure, meticulously determined using powder X-ray diffraction. We then correlated the experimental data with DFT-calculated isotropic shieldings. The small size of the unit cell of most amino acids allowed for advanced computations using various families of DFT functionals, including generalized gradient approximation (GGA), meta-GGA and hybrid DFT functionals. We tested several combinations of functionals for geometry optimizations and NMR calculations. For carbon shieldings, the widely used GGA functional PBE performed very well, although an improvement could be achieved by adding shielding corrections calculated for isolated molecules using a hybrid functional. For hydrogen nuclei, we observed the best performance for NMR calculations carried out with structures optimized at the hybrid DFT level. The high fidelity of the calculations made it possible to assign additional signals that could not be assigned based on experiments alone, for example signals of two non-equivalent molecules in the unit cell of some of the amino acids. Pracoviště Ústav organické chemie a biochemie Kontakt asep@uochb.cas.cz ; Kateřina Šperková, Tel.: 232 002 584 ; Jana Procházková, Tel.: 220 183 418 Rok sběru 2025 Elektronická adresa https://doi.org/10.1016/j.ssnmr.2024.101921
Počet záznamů: 1