Parallel stacking interactions in square-planar transition-metal complexes containing fused chelate and C6-aromatic rings
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Updated: May 22, 2026

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Published on: March 19, 2020
Dušan N Sredojević1, Dubravka Z Vojislavljević, Zoran D Tomić
1Innovation Centre, Department of Chemistry, University of Belgrade, Belgrade, Serbia.
Abstract:
Stacking interactions in the crystal structures of square-planar transition metal complexes from the Cambridge Structural Database with five- and six-membered chelate rings fused with C(6-arom) rings (arom = aromatic) were analyzed. The distribution of distances between the closest C(6-arom)-C(6-arom) and C(6-arom)-chelate contacts shows that in a large fraction of the intermolecular interactions the C(6-arom) ring of one molecule is closer to the chelate than to the C(6-arom) ring of the other molecule. These results indicate a possible preference of the C(6-arom) ring to form stacking contacts with the chelate rings. The preference is ubiquitous and does not depend on the metal type.
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