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Updated: Jul 15, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Theoretical evidence for a NH...XC blue-shifting hydrogen bond: complexes pairing monohalomethanes with HNO
Mohammad Solimannejad1, Steve Scheiner
1Quantum Chemistry Group, Department of Chemistry, Arak University, 38156-879 Arak, Iran. m-solimannejad@araku.ac.ir
Abstract:
Correlated ab initio calculations are used to analyze the interaction between nitrosyl hydride (HNO) and CH3X (X = F, Cl, Br). Three minima are located on the potential energy surface of each complex. The more strongly bound contains a NH...X bond, along with CH...O; CH...O and CH...N bonds occur in the less stable minimum. Binding energies of the global minimum lie in the range of 11-13 kJ/mol, and there is little sensitivity to the identity of the halogen atom. Unlike most other such hydrogen bonds, the NH covalent bond in this set of complexes becomes shorter, and its stretching frequency shifts to the blue, upon forming the NH...X hydrogen bond. The amount of this blue shift varies in the order F > Cl > Br.
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