Iodine Bonding Stabilizes Iodomethane in MIDAS Pesticide. Theoretical Study of Intermolecular Interactions between Iodomethane and Chloropicrin


The results are reported of a theoretical study of iodomethane (H3C-I, 1) and chloropicrin (Cl3C-NO2, 2), of the heterodimers 3-6 formed by aggregation of 1 and 2, and of their addition products 7 and 8 and their possible fragmentation reactions to 9-18. Mixtures of iodomethane and chloropicrin are not expected to show chemistry resulting from their reactions with each other. The structures and stabilities are discussed of the iodine-bonded molecular aggregates (IBMA) 3 and 4 and of the hydrogen- and iodine-bonded molecular aggregates (IHBMA) 5 and 6. The mixed aggregates 3-5 are bound on the free enthalpy surface relative to the homodimers of 1 and 2, and the IBMA structures 3 and 4 are most stable. This result suggests that the mixture of chloropicrin and iodomethane in the pesticide Midas is a good choice to reduce the volatility of iodomethane because of thermodynamically stabilizing iodine bonding.



Keywords and Phrases

chloropicrin; halogen bonding; intermolecular bonding; methyl iodide; pesticide; soil fumigant; UHF instability

International Standard Serial Number (ISSN)

0021-8561; 1520-5118

Document Type

Article - Journal

Document Version


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© 2012 American Chemical Society (ACS), All rights reserved.

Publication Date

01 Feb 2012