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
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
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1,3-二碘-5-硝基苯、1,3-二溴-5-硝基苯和1,3-二氯-5-硝基苯结构中紧密接触和相关分子间相互作用能的结构和计算比较
DOI：
10.1107/s2053229622009275
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Speetzen, Erin D.
中科院分区：
文献类型：
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作者：
Bosch, Eric;Bowling, Nathan P.;Speetzen, Erin D.
1，3-二碘-5-硝基苯（C6 H3 I2 NO2）和1，3-二溴-5-硝基苯（C6 H3 Br 2NO 2）在中心对称空间群P21/m中结晶，并且与1，3-二氯-5-硝基苯（C6 H3Cl 2NO 2）同构，为了一致性，在100 K下重新测定。 虽然所有三种结构中的三维堆积是相似的，但卤素原子的大小影响分子之间观察到的非键合紧密接触。因此，1，3-二碘-5-硝基苯的结构具有紧密的I型I → I接触，1，3-二溴-5-硝基苯的结构具有自互补的硝基-O → Br紧密接触，而1，3-二氯-5-硝基苯的结构也具有自互补的硝基-O → Cl相互作用，以及分叉的C-H → O（硝基）紧密接触。值得注意的是，三种结构中的每一种中的相邻分子之间的主要能量吸引分子间相互作用对应于π堆叠相互作用。自互补的卤素-H2O（硝基）和C-H-H2O（硝基）相互作用对应于每个结构中分子之间的显著内聚吸引力，而1型卤素-卤素接触是弱内聚的。
1,3-Diiodo-5-nitrobenzene, C6H3I2NO2, and 1,3-dibromo-5-nitrobenzene, C6H3Br2NO2, crystallize in the centrosymmetric space group P21/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.