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Updated: Mar 27, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Can the current density map topology be extracted from the nucleus independent chemical shifts?
Sofie Van Damme1, Guillaume Acke1, Remco W A Havenith2
1Ghent University, Faculty of Science, Department of Inorganic and Physical Chemistry, Krijgslaan 281, S3, 9000 Ghent, Belgium. patrick.bultinck@ugent.be and Members of the QCMM, Alliance Ghent-Brussels, Belgium.
Abstract:
Aromatic compounds are characterised by the presence of a ring current when in a magnetic field. As a consequence, current density maps are used to assess (the degree of) aromaticity of a compound. However, often a more discrete set of so-called Nucleus Independent Chemical Shift (NICS) values is used that is derived from the current density. It is shown here that there is no simple one-to-one relationship that allows reconstructing current density maps from only NICS-values. NICS values should therefore not be used as aromaticity indices without analysis of the ab initio computed current density map.
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