Xe-129 NMR chemical shift in Xe@C-60 calculated at experimental conditions: Essential role of the relativity, dynamics, and explicit solvent

0394735 - ÚOCHB 2014 RIV US eng J - Článek v odborném periodiku
Standara, Stanislav - Kulhánek, P. - Marek, R. - Straka, Michal
Xe-129 NMR chemical shift in Xe@C-60 calculated at experimental conditions: Essential role of the relativity, dynamics, and explicit solvent.
Journal of Computational Chemistry. Roč. 34, č. 22 (2013), s. 1890-1898. ISSN 0192-8651. E-ISSN 1096-987X
Grant CEP: GA ČR GA203/09/2037; GA ČR GA13-03978S
Grant ostatní: 7th European Community Framework Program(XE) FP7-286154; CEITEC-Central European Institute of Technology (European Regional Development)(XE) CZ.1.05/1.1.00/02.0068; Operational Program Research and Development for Innovations(XE) CZ.1.05/3.2.00/08.0144
Institucionální podpora: RVO:61388963
Klíčová slova: Xe-129 NMR * Xe@C-60 * dynamical averaging * explicit solvent * relativistic effects
Kód oboru RIV: CF - Fyzikální chemie a teoretická chemie
Impakt faktor: 3.601, rok: 2013

The isotropic Xe-129 nuclear magnetic resonance (NMR) chemical shift (CS) in Xe@C-60 dissolved in liquid benzene was calculated by piecewise approximation to faithfully simulate the experimental conditions and to evaluate the role of different physical factors influencing the Xe-129 NMR CS. The Xe-129 shielding constant was obtained by averaging the Xe-129 nuclear magnetic shieldings calculated for snapshots obtained from the molecular dynamics trajectory of the Xe@C-60 system embedded in a periodic box of benzene molecules. Relativistic corrections were added at the Breit-Pauli perturbation theory (BPPT) level, included the solvent, and were dynamically averaged. It is demonstrated that the contribution of internal dynamics of the Xe@C-60 system represents about 8% of the total nonrelativistic NMR CS, whereas the effects of dynamical solvent add another 8%. The dynamically averaged relativistic effects contribute by 9% to the total calculated Xe-129 NMR CS. The final theoretical value of 172.7 ppm corresponds well to the experimental Xe-129 CS of 179.2 ppm and lies within the estimated errors of the model. The presented computational protocol serves as a prototype for calculations of Xe-129 NMR parameters in different Xe atom guest-host systems.
Trvalý link: http://hdl.handle.net/11104/0223099