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Calculation of the diamagnetic component of the nuclear screening constant for C, N, O and F

✍ Scribed by K. A. K. Ebraheem; G. A. Webb; M. Witanowski

Publisher: John Wiley and Sons
Year: 1976
Tongue: English
Weight: 299 KB
Volume: 8
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270080610

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✦ Synopsis

Abstract

‘Local’ and ‘nonlocal’ contributions to σ^d^ are calculated by INDO molecular orbital methods. It is demonstrated, by means of Pople's approach^5^ using ‘gauge dependent’ atomic orbitals, that σ is effectively constant for C, N, O or F in a number of chemically different environments and that σ is negligible. The use of Flygare's method^12^ produces a significant and variable ‘nonlocal’ contribution, which renders σ^d^ in this formulation comparable to the gauge dependent term in Ramsey's expression.

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