Další formáty:
BibTeX
LaTeX
RIS
@article{1384906,
author = {Novotný, Jan and Vícha, Jan and Bora, Pankaj Lochan and Repisky, Michal and Straka, Michal and Komorovsky, Stanislav and Marek, Radek},
article_location = {Washington},
article_number = {8},
doi = {http://dx.doi.org/10.1021/acs.jctc.7b00444},
keywords = {NMR chemical shift; spin-orbit coupling; relativistic DFT; gold; platinum; mercury;},
language = {eng},
issn = {1549-9618},
journal = {Journal of Chemical Theory and Computation},
title = {Linking the Character of the Metal-Ligand Bond to the Ligand NMR Shielding in Transition-Metal Complexes: NMR Contributions from Spin-Orbit Coupling},
url = {http://dx.doi.org/10.1021/acs.jctc.7b00444},
volume = {13},
year = {2017}
}
TY - JOUR
ID - 1384906
AU - Novotný, Jan - Vícha, Jan - Bora, Pankaj Lochan - Repisky, Michal - Straka, Michal - Komorovsky, Stanislav - Marek, Radek
PY - 2017
TI - Linking the Character of the Metal-Ligand Bond to the Ligand NMR Shielding in Transition-Metal Complexes: NMR Contributions from Spin-Orbit Coupling
JF - Journal of Chemical Theory and Computation
VL - 13
IS - 8
SP - 3586-3601
EP - 3586-3601
PB - American Chemical Society
SN - 15499618
KW - NMR chemical shift
KW - spin-orbit coupling
KW - relativistic DFT
KW - gold
KW - platinum
KW - mercury;
UR - http://dx.doi.org/10.1021/acs.jctc.7b00444
L2 - http://dx.doi.org/10.1021/acs.jctc.7b00444
N2 - Relativistic effects significantly affect various spectroscopic properties of compounds containing heavy elements. Particularly in Nuclear Magnetic Resonance (NMR) spectroscopy, the heavy atoms strongly influence the NMR shielding constants of neighboring light atoms. In this account we analyze paramagnetic contributions to NMR shielding constants and their modulation by relativistic spin-orbit effects in a series of transition-metal complexes of Pt(II), Au(I), Au(III), and Hg(II). We show how the paramagnetic NMR shielding and spin-orbit effects relate to the character of metal-ligand (M-L) bond. A correlation between the (back)-donation character of the M-L bond in d10 Au(I) complexes and the propagation of the spin-orbit (SO) effects from M to L through the M-L bond influencing the ligand NMR shielding via Fermi-contact mechanism is found and rationalized by using third-order perturbation theory. The SO effects on the ligand NMR shielding are demonstrated to be driven by both the electronic structure of M and the nature of the trans ligand, sharing the sigma-bonding metal orbital with the NMR spectator atom L. The deshielding paramagnetic contribution is linked to the sigma-type M-L bonding orbitals, which are notably affected by the trans ligand. The SO deshielding role of sigma-type orbitals is enhanced in d10 Hg(II) complexes with Hg 6p atomic orbital involved in the M-L bonding. In contrast, in d8 Pt(II) complexes, occupied pi-type orbitals play a dominant role in the SO-altered magnetic couplings due to the accessibility of vacant antibonding sigma-type MOs in formally open 5d-shell (d8). This results in a significant SO shielding at the light atom. The energy- and composition-modulation of sigma- vs pi-type orbitals by spin-orbit coupling is rationalized and supported by visualizing the SO-induced changes in the electron density around the metal and light atoms (spin-orbit electron deformation density, SO-EDD).
ER -
NOVOTNÝ, Jan, Jan VÍCHA, Pankaj Lochan BORA, Michal REPISKY, Michal STRAKA, Stanislav KOMOROVSKY a Radek MAREK. Linking the Character of the Metal-Ligand Bond to the Ligand NMR Shielding in Transition-Metal Complexes: NMR Contributions from Spin-Orbit Coupling. \textit{Journal of Chemical Theory and Computation}. Washington: American Chemical Society, 2017, roč.~13, č.~8, s.~3586-3601. ISSN~1549-9618. Dostupné z: https://dx.doi.org/10.1021/acs.jctc.7b00444.
|
