✦ LIBER ✦

CNDO calculations of diamagnetic shielding in molecules

✍ Scribed by Andrzej J. Sadlej

Publisher: John Wiley and Sons
Year: 1970
Tongue: English
Weight: 372 KB
Volume: 2
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270020108

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✦ Synopsis

Abstract

An approximate procedure for the calculation of diamagnetic shielding in molecules is presented. The method proposed is based on the ‘complete neglect of differential overlap’ (CNDO) molecular wave functions and is formulated according to the zero differential overlap (ZDO) approximation. The results obtained with several CNDO‐type wave functions for diatomic and polyatomic molecules are in very good agreement with non‐empirical SCF calculations. The ^14^N diamagnetic shielding constants in several molecules were computed and some approximations usually adopted in the interpretation of ^14^N chemical shifts are critically discussed. It was shown that in some cases the observed ^14^N chemical shifts cannot be interpreted solely in terms of the paramagnetic contribution to the shielding constant.

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