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A Comparison of the Experimental and ab Initio Values of the17O NMR Chemical Shifts in the Carbonyl Group

✍ Scribed by Karol Jackowski; Michał Jaszuński; Włodzimierz Makulski

Publisher
Elsevier Science
Year
1997
Tongue
English
Weight
85 KB
Volume
127
Category
Article
ISSN
1090-7807

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✦ Synopsis

New experimental and theoretical results are presented for the

Whenever approximations are made, for example, a finite NMR shielding of oxygen in the carbonyl group. The experimental basis set is used, magnetic properties may depend on the values clearly demonstrate that the solvent effects are very signifiarbitrary gauge origin of the magnetic field. In all the apcant. The new results for the chemical shifts are in better agreeproaches discussed above, the computed shielding constants ment than the previous literature data with the corresponding ab are gauge invariant since GIAOs (gauge invariant atomic initio values calculated for isolated molecules. ᭧ 1997 Academic Press orbitals) are used within the linear response formalism. Another advantage of the GIAOs is that, as shown by many numerical results (see, e.g., (10-12)), the convergence to 139

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