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Basis set and correlation effects in the calculation of selenium NMR shieldings

✍ Scribed by Gábor Magyarfalvi; Peter Pulay

Publisher
Elsevier Science
Year
1994
Tongue
English
Weight
351 KB
Volume
225
Category
Article
ISSN
0009-2614

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✦ Synopsis

Accurate ab initio GIAO calculations of "Se chemical shieldings in SeHs, SeHCH3 and Se(CH,)2 are reported. The calculations closely reproduce the experimental relative chemical shifts of these molecules. The extension of the basis sets with p, d and f functions on the selenium atom improves the chemical shifts at the SCF level values, but quantitativeness is only achieved at the MP2 level. The effect of conformation on the chemical shieldings is also discussed.

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