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  • A structural and computational comparison of close contacts and related intermolecular energies of interaction in the structures of 1,3-diiodo-5-nitrobenzene, 1,3-dibromo-5-nitrobenzene, and 1,3-dichloro-5-nitrobenzene
Title: A structural and computational comparison of close contacts and related intermolecular energies of interaction in the structures of 1,3-diiodo-5-nitrobenzene, 1,3-dibromo-5-nitrobenzene, and 1,3-dichloro-5-nitrobenzene

1,3-Diiodo-5-nitrobenzene, C6H3I2NO2, and 1,3-dibromo-5-nitrobenzene, C6H3Br2NO2, crystallize in the centrosymmetric space groupP21/m, and are isostructural with 1,3-dichloro-5-nitrobenzene, C6H3Cl2NO2, that has been redetermined at 100 K for consistency. While the three-dimensional packing in all three structures is similar, the size of the halogen atom affects the nonbonded close contacts observed between molecules. Thus, the structure of 1,3-diiodo-5-nitrobenzene features a close Type 1 I...I contact, the structure of 1,3-dibromo-5-nitrobenzene features a self-complementary nitro-O...Br close contact, while the structure of 1,3-dichloro-5-nitrobenzene also has a self-complementary nitro-O...Cl interaction, as well as a bifurcated C—H...O(nitro) close contact. Notably, the major energetically attractive intermolecular interaction between adjacent molecules in each of the three structures corresponds to a π-stacked interaction. The self-complementary halogen...O(nitro) and C—H...O(nitro) interactions correspond to significant cohesive attraction between molecules in each structure, while the Type 1 halogen–halogen contact is weakly cohesive.

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Award ID(s):
2108202 1903593 1903581
NSF-PAR ID:
10470764
Author(s) / Creator(s):
; ;
Publisher / Repository:
International Union of Crystallography
Date Published:
Journal Name:
Acta Crystallographica Section C Structural Chemistry
Volume:
78
Issue:
10
ISSN:
2053-2296
Page Range / eLocation ID:
552 to 558
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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