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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Reactions between cold methyl halide molecules and alkali-metal atoms
Jesse J Lutz1, Jeremy M Hutson1
1Joint Quantum Centre (JQC) Durham-Newcastle, Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom.
Abstract:
We investigate the potential energy surfaces and activation energies for reactions between methyl halide molecules CH3X (X = F, Cl, Br, I) and alkali-metal atoms A (A = Li, Na, K, Rb) using high-level ab initio calculations. We examine the anisotropy of each intermolecular potential energy surface (PES) and the mechanism and energetics of the only available exothermic reaction pathway, CH3X + A → CH3 + AX. The region of the transition state is explored using two-dimensional PES cuts and estimates of the activation energies are inferred. Nearly all combinations of methyl halide and alkali-metal atom have positive barrier heights, indicating that reactions at low temperatures will be slow.
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