Abstract
Molecular symmetry is a key parameter which dictates the NMR chemical shielding anisotropy (CSA). Whereas correlations between specific geometrical features of molecules and the CSA are known, the quantitative correlation with symmetry - a global structural feature - has been unknown. Here we demonstrate a CSA/symmetry quantitative relation for the first time: We study how continuous deviation from exact symmetry around a nucleus affects its shielding. To achieve this we employed the continuous symmetry measures methodology, which allows one to quantify the degree of content of a given symmetry. The model case we use for this purpose is a population of distorted SiH 4 structures, for which we follow the 29Si CSA as a function of the degree of tetrahedral symmetry and of square-planar symmetry. Quantitative correlations between the degree of these symmetries and the NMR shielding parameters emerge.
Original language | English |
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Pages (from-to) | 8534-8538 |
Number of pages | 5 |
Journal | Chemistry - A European Journal |
Volume | 12 |
Issue number | 33 |
DOIs | |
State | Published - 15 Nov 2006 |
Keywords
- Chemical shifts
- NMR spectroscopy
- Silicon
- Symmetry
- Tensors