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Updated: Sep 22, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Weakly Bound Complex Formation between HCN and CH3Cl: A Matrix-Isolation and Computational Study
Emily K Hockey1, Korina Vlahos1, Thomas Howard1
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States.
Abstract:
The matrix-isolated infrared spectrum of a hydrogen cyanide-methyl chloride complex was investigated in a solid argon matrix. HCN and CH3Cl were co-condensed onto a substrate held at 10 K with an excess of argon gas, and the infrared spectrum was measured using Fourier-transform infrared spectroscopy. Quantum chemical geometry optimization, harmonic frequency, and natural bonding orbital calculations indicate stabilized hydrogen- and halogen-bonded structures. The two resulting weakly bound complexes are both composed of one CH3Cl molecule bound to a (HCN)3 subunit, where the three HCN molecules are bound head-to-tail in a ring formation. Our study suggests that─in the presence of CH3Cl─the formation of (HCN)3 is promoted through complexation. Since HCN aggregates are an important precursor to prebiotic monomers (amino acids and nucleobases) and other life-bearing polymers, this study has astrophysical implications toward the search for life in space.
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