On the stability of clathrate hydrates encaging polar guest molecules: contrast in the hydrogen bonds of methylamine and methanol hydrates

Kenichiro Koga, Hideki Tanaka, Koichiro Nakanishi

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11 Citations (Scopus)


The stability of clathrate hydrates encaging highly polar guests has been investigated in order to explain the experimental observation that some amines form clathrate hydrates but alcohols act as inhibitor to hydrate formation. We choose methylamine and methanol as guest species and examine the stable structure, at which the total potential energy has a minimum value. At the local minima of those two hydrates, the potential energies of water-water and guest-water, and their hydrogen bonded networks are compared. It is found that methanol does not retain the host lattice structure, while the host-network structure is kept in the presence of methylamine. It is shown that the difference in the magnitude of the partial charge on the hydrogen atom between the hydroxyl and amino groups plays a much more significant role on the stability of both clathrate hydrates than the difference in molecular geometry. This is supported from the result of a methylamine-like model that has the same partial charges on the atoms in the hydrophilic site as methanol.

Original languageEnglish
Pages (from-to)241-252
Number of pages12
JournalMolecular Simulation
Issue number3-6
Publication statusPublished - 1994
Externally publishedYes


ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

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