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@article{987442,
author = {Lantto, Perttu and Standara, Stanislav and Riedel, Sebastian and Vaara, Juha and Straka, Michal},
article_location = {Cambridge},
article_number = {31},
doi = {http://dx.doi.org/10.1039/C2CP41240C},
keywords = {COUPLED-CLUSTER CALCULATIONS; DENSITY-FUNCTIONAL CALCULATIONS; RESONANCE SHIELDING TENSORS; NOBLE-GAS ATOMS; RARE-GAS; AB-INITIO; SPECTROSCOPIC PARAMETERS; NUCLEAR SHIELDINGS; MATRIX-ISOLATION; NMR PROPERTIES},
language = {eng},
issn = {1463-9076},
journal = {Physical Chemistry Chemical Physics},
title = {Exploring new 129Xe chemical shift ranges in HXeY compounds: hydrogen more relativistic than xenon},
url = {http://pubs.rsc.org/en/content/articlelanding/2012/cp/c2cp41240c},
volume = {14},
year = {2012}
}
TY - JOUR
ID - 987442
AU - Lantto, Perttu - Standara, Stanislav - Riedel, Sebastian - Vaara, Juha - Straka, Michal
PY - 2012
TI - Exploring new 129Xe chemical shift ranges in HXeY compounds: hydrogen more relativistic than xenon
JF - Physical Chemistry Chemical Physics
VL - 14
IS - 31
SP - 10944-10952
EP - 10944-10952
PB - Royal Society of Chemistry
SN - 14639076
KW - COUPLED-CLUSTER CALCULATIONS
KW - DENSITY-FUNCTIONAL CALCULATIONS
KW - RESONANCE SHIELDING TENSORS
KW - NOBLE-GAS ATOMS
KW - RARE-GAS
KW - AB-INITIO
KW - SPECTROSCOPIC PARAMETERS
KW - NUCLEAR SHIELDINGS
KW - MATRIX-ISOLATION
KW - NMR PROPERTIES
UR - http://pubs.rsc.org/en/content/articlelanding/2012/cp/c2cp41240c
L2 - http://pubs.rsc.org/en/content/articlelanding/2012/cp/c2cp41240c
N2 - Among rare gases, xenon features an unusually broad nuclear magnetic resonance (NMR) chemical shift range in its compounds and as a non-bonded Xe atom introduced into different environments. In this work we show that 129Xe NMR chemical shifts in the recently prepared, matrix-isolated xenon compounds appear in new, so far unexplored 129Xe chemical shift ranges. State-of-the-art theoretical predictions of NMR chemical shifts in compounds of general formula HXeY (Y = H, F, Cl, Br, I, -CN, -NC, -CCH, -CCCCH, -CCCN, -CCXeH, -OXeH, -OH, -SH) as well as in the recently prepared ClXeCN and ClXeNC species are reported. The bonding situation of Xe in the studied compounds is rather different from the previously characterized cases as Xe appears in the electronic state corresponding to a situation with a low formal oxidation state, between I and II in these compounds. Accordingly, the predicted 129Xe chemical shifts occur in new NMR ranges for this nucleus: ca. 500-1000 ppm (wrt Xe gas) for HXeY species and ca. 1100-1600 ppm for ClXeCN and ClXeNC. These new ranges fall between those corresponding to the weakly-bonded Xe0 atom in guest–host systems (>300 ppm) and in the hitherto characterized Xe molecules (<2000 ppm). The importance of relativistic effects is discussed. Relativistic effects only slightly modulate the 129Xe chemical shift that is obtained already at the nonrelativistic CCSD(T) level. In contrast, spin–orbit-induced shielding effects on the 1H chemical shifts of the H1 atom directly bonded to the Xe center largely overwhelm the nonrelativistic deshielding effects. This leads to an overall negative 1H chemical shift in the range between -5 and -25 ppm (wrt CH4). Thus, the relativistic effects induced by the heavy Xe atom appear considerably more important for the chemical shift of the neighbouring, light hydrogen atom than that of the Xe nucleus itself. The predicted NMR parameters facilitate an unambiguous experimental identification of these novel compounds.
ER -
LANTTO, Perttu, Stanislav STANDARA, Sebastian RIEDEL, Juha VAARA a Michal STRAKA. Exploring new 129Xe chemical shift ranges in HXeY compounds: hydrogen more relativistic than xenon. \textit{Physical Chemistry Chemical Physics}. Cambridge: Royal Society of Chemistry, roč.~14, č.~31, s.~10944-10952. ISSN~1463-9076. doi:10.1039/C2CP41240C. 2012.
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