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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
A new unconventional halogen bond C-X...H-M between HCCX (X = Cl and Br) and HMH (M = Be and Mg): an ab initio study
Qing-Zhong Li1, Xu Dong, Bo Jing
1The Laboratory of Theoretical and Computational Chemistry, Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, People's Republic of China. liqingzhong1990@sina.com
Abstract:
In this article, a new type of halogen-bonded complex YCCX...HMY (X = Cl, Br; M = Be, Mg; Y = H, F, CH(3)) has been predicted and characterized at the MP2/aug-cc-pVTZ level. We named it as halogen-hydride halogen bonding. In each YCCX...HMY complex, a halogen bond is formed between the positively charged X atom and the negatively charged H atom. This new kind of halogen bond has similar characteristics to the conventional halogen bond, such as the elongation of the C-X bond and the red shift of the C-X stretch frequency upon complexation. The interaction strength of this type of halogen bond is in a range of 3.34-10.52 kJ/mol, which is smaller than that of dihydrogen bond and conventional halogen bond. The nature of the electrostatic interaction in this type of halogen bond has also been unveiled by means of the natural bond orbital, atoms in molecules, and energy decomposition analyses.
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