Friday, May 19, 2006

Chemical Physics: 17O and 1H shielding calculations

Comment: Cory, looks like someone beat you to the discovery of 17O CSA in water.

Volume: 323, Issue: 2-3 April 21, 2006
pp. 218-230
On the calculations of the nuclear shielding constants in small water clusters
Hubert Cybulski, Joanna Sadlej
, Department of Chemistry, University of Warsaw, Pasteura 1,

The comparative study of the calculated ab initio 17 O and 1 H shielding constants for water clusters (H2 O)n, n = 2–6, 12 and 17, is presented. The comparison of different methods and the convergence of a basis set size were analyzed to enable the choice of the most efficient method of calculations. DFT(B3LYP)/aug-cc-pCVDZ calculations of shielding constants were performed for all clusters under the study. The correlation of the changes in the 1 H shielding constants on intra- and intermolecular distances was observed. The changes of the 17 O shielding constants depend strongly on the cluster size and its hydrogen-bonding topology. The largest shift (−76.2 ppm) was found for the central oxygen atom surrounded by two hydration shells in the largest water cluster, (H2 O)17. The interaction-induced changes in the 17 O shielding constants are found to be non-additive.

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